I've got a jeep here, appointment in about half an hour, sight at last, I'm going to see the jeep, he's happy. That's Lydia, what's up with her in the morning? Yeah, how are you? I'm going to ask Cardiola for a drink or two collection in the building, enjoying myself in my surprisingly cold bedroom. I'm just talking to Kyle on Instagram, one of these vlogs will be way better, I promise. I just had 20 minutes when I couldn't find my phone. I forgot to put my phone where I was, until it hit the phone. So I haven't done much today, all I've done is have enough for five hours. I needed the sleep, I don't know what to do. But yeah, this has been a real life, I hope you enjoyed it.


Okay guys, good morning. Good morning. Yeah happy Monday morning Did it scare you is that what you were saying all those people come into your door Okay, so hopefully everybody had a happy Halloween yesterday got a lot of candy Got a lot of studying. Yeah, I saw you were online very late last night Okay, anyways Ladies and gentlemen, if you don't mind Everybody came to hear me talk today not each other, right? So yeah, so we might as well get started with listening to me, right? Okay, so if you recall Last time we talked about reaction rate This was a problem that was given at the end of lecture last time Okay, so a solid Sodium was put into pure water all the sodium had reacted after eight seconds And the concentration was found to be 0.001 3 molar how do you figure out this problem? So let's go ahead and figure out. Well, what's the average rate here? All right, so what is the formula say so it says the concentration of a2 minus the concentration of a1 so concentration a2 so this is concentration of a at time 2 Minus the concentration of a at time 1 and remember this is the general reaction a goes to be so we're looking at the reactants here, okay, and we want to do Change of time, so we're going to do time 2 minus time 1 And then we say And then let's figure out what these variables are so what's concentration a1 What is that going to be does anybody know? Since everybody did this problem over the weekend like we were supposed to write Everybody should be telling me what's going on. So what's concentration a1? Okay, good job guys. So why don't you guys do this on your own? and We'll go over it tomorrow when you guys can tell me what the answers of this are okay Okay, so let's start talking about reaction mechanism then So a reaction mechanism is step-wise changes that reactants undergo in their conversion to products Okay, I'll show you a reaction mechanism And we want to think about So I'll erase this stuff. So if we think about reactions going from a to b okay We briefly mentioned this at the end of last period That a reaction going to a and b that's just like watching a Race but not watching what happens in the middle That's only watching what happens at the beginning of the race and at the end of the race So it's like two snapshots like what's the starting order and who won? Okay, but a lot of interesting stuff could happen in between the beginning and the end of a race right I can imagine like I Don't know like a NASCAR race or something like that probably people Watch it more often than not to see what happens in between What happens at the starting and the ending point right then they enjoy watching what happens in the middle Okay, yeah people wreck right so that would be like the Reaction mechanism, okay, so what we've been showing so far is just watching Okay, so this is what happened at the beginning. This is what happened at the end. That's not very interesting Okay, so let's start talking about what happened in the middle. Okay? so what could happen in the middle is a Could go to like intermediate one and then intermediate one could go to intermediate two Intermediate two could go to Intermediate three so on and so forth Until we get to be okay So if we just took these two snapshots We wouldn't know anything about intermediate one two and three. Okay, just to beat a dead horse Okay, so the stepwise changes that the reactants undergo on their way to conversion to products So a reaction mechanism often is expressed as a number of processes that must take place for these reactions to occur So we got to make a few assumptions when we're talking about reactions Okay, so the first assumption is that the reactant particles must collide with one another in order for a reaction to occur Okay, they can't just shout at each other and react Okay, they actually have to come into contact with each other With enough speed to smash into each other break bonds and form bonds Okay, so the reactant particles must collide with one another In order for the reaction to occur this of course is if you have two reactant particles For a decomposition reaction, of course, you're only going to have one reactant, right? So you don't need it to smash into anything else. You just need to give it enough energy to for those bonds to break Okay, this is the assumption that we're talking about if we have something more than one reactant, right? But anyway, so molecules can't react with each other if they don't come into contact with each other and During collisions some bonds are broken Atoms are exchanged and new bonds are formed. Okay, let's look at a proper reaction mechanism So We'll look at Bromo methane Reacting with sodium hydroxide to make methanol. Okay. Let's look at this reaction So you guys remember what a wedge bond means, right? Okay, and a dash bond, you know that too, right? Okay, cool. Okay, so the reaction that I'm going to write here is going to be CH3Br This is the liquid plus NaOH We can make this aqueous goes to CH3OH Plus Na, oops CH3OH liquid plus MABR Aqueous is good enough for me Okay So when we put NaOH into water Everybody probably understands hopefully that it's going to dissolve into water breaking into its two constituent ions Na and OH Okay So if you really wanted to think about it that would be the first step of the reaction mechanism But not the reaction mechanism proper. Okay, because the OH is the only thing that really reacts So we're going to have floating around in solution and Na plus ions and OH minus ions like that Here let's just draw this bond out Okay, so this reaction that we're about to do is not like this reaction where there's One two three four five or whatever steps. Okay, this is a one-step reaction But you can actually see the reaction mechanism So what's going to happen is? The electrons on this oxygen are going to want to attack That carbon there smash into it like that and knock this bond But you can really this really emphasizes what happens. We're Making a bond and we're breaking a bond. Okay, so let's look at the way that we've made the bond and broke the bond okay, so Hopefully everybody can see that we've made a bond in between this oxygen and that carbon. Okay, we've also Broken a bond Between that carbon and that bromine. We broke that bond there So this is a one-step mechanism All that happens is the one piece smashes into the other piece and knocking the Third piece away. Okay, so can everybody see what's going on here and see how we're Describing what is actually happening during the reaction as opposed to just saying what we set up here This now this Okay, so now we're actually saying this is how this molecule came into being right That makes sense, right? This is like a boxing match right instead of just watching two people stand here And then one person fall down right or one person on the ground you can see the actual punch that happened Okay to knock the person down. This would be the punch that happened So here we're seeing here the reactant particles Collide with one another these arrows are describing the motion of these reactant particles We're showing the bonds being broken right here. We see this bond is being broken We see this bond is being formed Okay, so we also assume that the reactant particles collide with a certain amount of energy So the reaction will occur if they don't if you it's like in the boxing match if the guy just taps the other guy It's not going to fall down right so you got to have enough energy to knock the guy out And in some cases reacting particles must be oriented in a specific way for the reaction to occur So like for this reaction This reaction only will occur if this oxygen hits this carbon at this spot if this oxygen came over here Whoops And ran into that bromine right there this reaction wouldn't occur Okay, because this oxygen wants to make a bond with this carbon if it's hitting it here It can't make a the reaction. It's like the boxing Analogy again, right if the boxer that wanted to win hit the other boxer on his foot, right? Probably wouldn't knock him out. Okay, so you got to hit him in the right spot. Okay, not in the little toe Okay So what we've just described is known as an effective collision okay So at all temperatures above absolute zero bonded atoms of molecules vibrate and stretch Okay, so what happens is you can see the bond here This is the average length of the bond, but when you've got some sort of temperature involved they kind of Stretch and bend and do all weird stuff. Okay, but they don't stretch enough to where the bond breaks Okay, so a bond is like kind of like I don't know Like a spider web or something that you that you get stuck to your hand, right? So when you get stuck to your hand, right? You pull it and pull it and pull it until it breaks Okay, and that's when the reaction occurs. Okay, but what happens is they can pull and stretch and bend without Actually breaking. Okay, and this is the actual total energy that the molecule actually has within it Okay, so when we talked about bonds being stored chemical energy That's what they're doing is using that energy just bouncing back and forth. Okay Kind of not really though metal is not covalent bonded together Okay, so you got to think of things that are covalently bonded together. That's why the Ozone layer shields us from UV radiation in the Sun is because when the Sun's UV radiation Hits that ozone it instead of you know breaking to form oxygen What happens it just stretches a little bit and then goes back so it absorbs that energy Okay, so this is covalent bonding. We're talking about not Metallic bonding or ionic bonding This is also like why You see colors Okay, so the colors are Absorbing that light and then reflecting Reflecting the light that they're not absorbing back and that's the colors like your shirts Not absorbing purple and your shirts not absorbing green. Okay, that's why we see those colors Okay, but this is what happens in covalent molecules. They stretch and bend and do all this stuff So they have a certain amount of internal energy is what we call that. Okay This internal energy can be increased by Collisions, okay, so it's just like you can imagine You know you can pull something apart harder or push it together harder and that's giving it even more energy So this Results in more vibration more vibration more vibration until the thing actually breaks Okay So if it breaks then we call that a reaction. Okay So it's not anything special. We have all these special names for all of this mundane things that actually are happening So if we look at this reaction here CH4 and O2 Are the reactants? So we'll do a less detailed analysis than we have done here But we got CH4 Notice this is the Lewis structure that I'm drawing here and O2 Like that Okay. Well, we've got two O2 molecules like that We call it a reaction Right Okay, so what happens? Whoops CO2 H2O Okay, so plus some energy So are these molecules on the left side of this arrow the same as on the right side of the arrow? No, what about everybody else that said didn't say anything No, right, so hopefully everybody can see that the left side and the right side are different. Okay, so But what is the same on the left and the right side? What is the same? So the elements specifically what that there is carbon hydrogen and oxygen? Okay, that's the same. What else is the same? The number of the Specifically yeah, that's what I was looking for right is that the number of atoms The particular atoms is the same on the left and the right side of the equation, right? but What's different about them? Yeah, so they're so Another way to say that right maybe in more layman's type terms is that They're arranged differently, right? They're all arranged differently Okay, so what must have happened from going from here to here? Bonds bonds had to be broken in this thing here, right because there's none of that stuff over here Right and since there's only got one carbon here and one carbon here We know that that carbon must have had some Oxygen's react with it right and also have those hydrogen somehow fall off of it and those hydrogens Since they're not attached to that carbon anymore, but are attached to this is oxygen's over here Something must have happened right so like was said bonds were must have been destroyed and Created or broken and formed right? so in this case the CH single bond was broken and the O double bond was broken O2 double bond was broken and The C double bond O was formed and the OH bond was formed too So energy is required to break the bonds. We'll talk about this in more detail in a second This energy comes from the collision of the molecules, okay? so it's just like the collision of the Boxers hand to the jaw of the other boxer that gives the energy to knock the guy out Right the energy that comes from the Are the it's necessary to break those bonds comes from the things? Smashing into each other and we call this an effective collision okay, so Why does any reaction occur? Okay, so this is is the next question. Why do these reactions occur to begin with? Can anybody think of a reason why reactions occur? There's no wrong answers right now. Well, I mean there's wrong answers, but don't worry about it But don't worry about getting them wrong. Okay, so can anybody think of any reason why a reaction would occur? Okay, so okay. Yeah, so okay I see what well the you guys are thinking of things in a different way than I am so you're thinking if I've got some stuff here How do I make these things react? That's the way you're thinking. I'm thinking generally, okay? So why why will they react if they're there? Kind of yeah, that's one kind of reason They'll hit each other. Yeah, that's kind of that temperature thing again but Okay, so and that's all right. That's all right. Okay, so in the universe I think we've talked about this that things always want to go down in energy. Okay, so since uh If you I guess if I want to say it right if I've got a Couple of things that will react together Okay, the reason that they'll react together is because the thing that they'll form is going to be at a lower overall Energy state than they are already. Okay So That's what's being shown right here. Okay, so Normally you'll see reactions spontaneous reaction specifically Where the reactants overall energy is significantly higher than the products overall energy? Okay, it's like Why does something fall down? Why doesn't it if I just put this here? Why does it just stay there? Yeah, but I mean gravity what it would that doesn't mean anything to me. Tell me more about gravity. What is happening here, huh? Okay, so it's an attractive force, right? There's an attractive force. So okay, so do I have more attraction that when I'm way up here or More attraction when I'm up here or down here. Well, it's what it what happens when it gets to the center Then that must be the last least attractive force. Is that what you're saying? If that's the least attractive force when they bounce away from each other If it's the least amount of attraction, that's like what's the most amount of attraction? It's like when they're stuck together, right? That's gonna be the most amount of attraction, right? If they're things that are not attracted to each other if they're like next to each other, what do they do? Bounce away from each other, right? Okay Yeah, so it wants to go this way, right? So it's like if I have a positive and a negative thing. What's gonna happen? They're gonna want to stick together, right? It's the same kind of thing with gravity. Although. It's not a positive negative thing Okay, so why is that? Why does it go from here to here? How about that? Let's talk about energy Yeah, how is it releasing energy? So what is this when from here to here? The difference is what? This has more What kind of energy? No, not gravity This energy, this energy, what is it called? What are the two kinds of energy? How about that? Kinetic and potential energy, okay. What are we talking about in this? Chapter, what are we talking about in this chapter? Kinetics, okay, so what is that the study of? No, we've talked about this. Okay. What's kinetics? Don't guess. What's kinetics the study of? Okay, and when we're talking Kinetics specifically is the talk topic of rates, okay, rates Okay, so Potential or kinetic energy do you think this has? So where is the kinetic energy when I'm talking about potential and kinetic energy of this system? Okay, so Okay, but so what's this got very high and this has got low what? high Potential energy why? Because it could potentially fall down, right? That's why it's got high potential energy. That's all it means, okay? Kinetics is the study of what? Rates, okay, so you could kind of think its kinetic energy is increasing as it's falling, okay? Hey, when it's doing stuff, when you're doing stuff your kinetic energy increases. Does that make sense? That should make sense to you, okay? If you don't know what the, what chapter we're talking, what we're talking about in the chapter, then it's probably going everything I'm saying is probably not registering and text messaging probably won't help you find the answer either. But anyways, okay, so what you want to always think of I'm serious. A lot of people think text messaging does help them find the answer. Anyways, what you want to think of is that the reactants are always going to be or not always in spontaneous reactions reactants are going to be at a higher energy level than products. Why, why do reactions want to occur? How about that? Let's let's ask this question again. Why do reactions want to occur? Yeah, because they want to be at a lower energy or the products are more stable than the reactants or the reactants are more what, than the products? Unstable or energetic, right? Okay, so they have more energy associated with them. Okay, so let's look at, so we're going to start writing reaction diagrams or potential energy diagrams. Okay, the same thing. Reaction diagrams, potential energy diagrams. When we have a spontaneous reaction, the reactants are going to be up here. The products are going to be down there. And we're going to lose energy. When we lose energy, do you remember I said this thing at the end has energy also?  Okay? Okay, so what's happening in this reaction? When I say it's giving off energy, what do you think is what I'm, what am I feeling? Heat, heat, right? This is like, if you do this reaction, you can boil water, right? Because this is the reaction of the Bunsen burner. Okay, yeah, it's an exothermic reaction. Okay, so that's what we're talking about here. I don't know who, if we've talked about exothermic yet, but we can start. We call this an exothermic reaction because heat is one of the products. We can also tell that because the reactants are at a higher energy state than the products. Okay? So in order, so remember the only thing that's different between this side and this side is that they're connected to different things, right? So it's not like we're getting rid of some of these things to lower the energy, right? We're not saying, okay, now we don't have this carbon atom anymore. Okay? So how are we getting, what's happening? Where's all this energy going? Right? That's the question I just asked. That's the question I just asked and you answered it in a different way. You said that you're feeling the energy come off as heat, okay? So that's what actually happens is that the reaction will get hot, okay? In this case, it'll produce fire, you know? And keep going until you get rid of the reactants, okay? But also, when you do the Bunsen-Bernard reaction or the same reaction as like turning on a gas stove, if you guys got a gas stove at home, when I mix oxygen and methane, okay? Does just the mixture of oxygen and methane start on fire and get the reaction going? No. No, what do you have to do to it? You can't just mix those things together and then expect it to go. You have to give it a spark. You have to give it a spark. Yeah, you got to activate it. Very good. Yeah, you got to activate it, okay? So you've got to give it a bit of external energy, okay? It's like the first time you were on the diving board or something, right?  Because you had a lot of potential energy and now you went down in energy. That's a spontaneous reaction as we know falling, right? Like this. This is a spontaneous reaction. Why isn't the chalk falling right now? Because I got energy. I'm giving it energy. I'm like not letting it go, okay? So once I let it go, bam, that's like the activation of it, okay?  I don't have a little brother, but pushing my little somebody off of the diving board. The kittens, yeah, off the diving board, okay? So here we've got So this is your reaction, your reactants, average energy. So they're just chilling like in your beaker just chilling, okay? Or they're coming out of the tube, you're smelling. It's like really smelly of rotten eggs because they just keep coming, methane and methane and methane out of there. And somebody's like, you need to like spark that thing before we all blow up, right? Then you're like, oh, that's what I haven't done, right? You know? So you get your sparker, ping, okay? You spark it. That's your activation energy, okay? So notice this, so this axis here, this y-axis is energy, okay? So we're, this is low energy. This is high energy. This is even higher energy, okay? This axis here is time or reaction progression. This is the beginning of the reaction. This will be the end of the reaction. Okay? So activation energy, we call that, and then it just goes down to products. Okay, so let's mark the activation energy. So it's from where the reactants started, all the way up to the top there. Okay, we call that the activation energy, and its symbol is EA, like that. So this is activation energy. Oh, it's just, you can think of it as like, this is how they always write it, the first letter, the first word at the bottom. But you can think of it as the energy of activation. Okay, so let's talk about an energy diagram specifically. Okay, so an energy diagram states the energy relationship for the reaction that are illustrated graphically by diagrams in which the energy of reaction is graphed on the vertical axis, like we have here, and the progress of the reaction, or over time, is on the horizontal axis. Okay, notice, also this also shows another energy, and that's this energy, from here to here. That's the difference between the reactants and the products. And remember, in this reaction, we said we're getting heat out of it. It was 211 kilojoules or something like that. That is this energy here, and we refer to that as delta H. You can think of H as heat, delta H as the change in heat. Okay, but this stands for this new term called enthalpy. Okay, so this is the enthalpy, I'll write it down. But you can think of it as the change in heat. So delta H is N, so that's just the energy difference between the reactants and products. So let's just make this a little better here, like that. Okay, so here you go, here's another common activation energy that you might be familiar with. Maybe if you guys had a jack-o'-lantern last night and lit a match to put a candle inside of it, you know, that lighting of the match is the activation energy. Of course, the match has a bunch of stored potential energy in it. How do you know that? What does it do? Yeah, it not only sparks, but like burns and it'll burn stuff, right?  If you throw it on like, you know, other things, it'll burn them up, right? It's got a bunch of energy in it, right? But you could keep it in a cardboard box, right? That's crazy. That is insane, right?  Why is that? Because we haven't given it its activation energy yet, okay? So that activation energy is what it takes to get sparked. And what do you think? The reactants on the tip of the match or the products of that reaction have more energy in them. The reactants? The reactants on the tip or the products after it's done? The reactants have much more energy. How do you know that? Oh, yeah, all of those things, right? What happens? What happens? It gives off heat, you strike it, it does that. What happens if you strike the match after it's done burned up? Nothing. Nothing will happen. Yeah, it'll break all apart, right? Okay. So in some reaction mixtures, the average total energy of the molecules is too low at the prevailing temperature for the reaction to take place at a detectable rate. This or the reaction mixture is said to be stable. For many stable mixtures, addition of a small amount of energy, just like our match, starts the reaction and continues without the addition of any more stimulus from an outside source until you use up your reactants, of course. And then the small amount of outside energy needed to spark these spontaneous things are activation energy. And then here's the match example. Okay, so you can go back to this energy diagram, the activation energy, the minimum amount of energy required to initiate the chemical reaction. You want to become familiar with the exothermic reaction, because we've gone over it quite a bit for quite a bit of a lecture today. Okay, so here's a difference in two reactions. Notice this. This guy's got a low activation energy. So this stuff is almost unstable at those conditions, okay? Right? If you put this stuff at just a little higher temperature, what would happen? It would react, right? Because what is energy and temperature like what? The same. The same, okay? So if we increase the energy here or increase the temperature, right, this stuff would react, okay? But this stuff, if we increase the temperature just a little bit, would it react? No. What about a little bit more? No, no. Because it's got a very high activation energy, okay? That makes sense, right? Okay, good. Notice here, which has the bigger delta H of these A or B, A or B. A, right? If you don't know how to do that, watch the lecture again, okay? Okay, so this reaction is known as an exothermic reaction. Why is that? It's because the reactants are at a higher energy level than the products. So the reactants have more potential energy than the products do, okay? This is also an exothermic reaction, showing, notice, the reaction mechanism at the top here, okay? The interesting thing, or not the reaction mechanism, we call this thing here the activated complex, okay? So the activated complex is an intermediate, okay? Or a transition state, I should say, a transition state. So this thing doesn't actually exist. It's the transition state between the thing forming and breaking bonds, okay? So if we were to look at our example from earlier, the transition state would be where we've got the carbon, the three hydrogens, and the bond that's about to break, really long and about to break, and the other bond that's about to form, really long and about to form, okay? This is the transition state. Notice this isn't a molecule, okay? This thing doesn't actually exist. This is like the snapshot of the boxer like hitting the other boxer, like right under the chin, mouthpiece coming out, all of that stuff. You know, this is that analogy, okay? So at the top of the, so here at the top, you'll get what we call the transition state, okay? Transition state. That's the transition from the reactants to the products. And notice you can see the kind of dashed bonds here that's partial bonds. Notice this says because it's got a large activation energy, it takes a long time for this reaction to progress, okay? Notice the transition state here. Notice the delta H. Notice the activation energy. Well, they have it as the reverse activation energy, so they're looking at it going from oxygen to, so they're saying that this is the reactants here, okay? And the last thing we want to talk about today before we get to leave is the opposite type of a reaction, where the reactants that are at a lower energy state than the products. Notice the activation energy of these reactions is very high, from way down there to way up there. Water freezing? Well, it's not really a reaction. That's a good example of an endothermic process. Well, not water freezing, water melting actually does it. It's kind of a logic little to think about, but it's pretty interesting. We'll talk about it next time, okay? So you can see the transition state of this one. Endothermic reaction, notice the high activation energy. Notice in endothermic reactions, your activation energy is going to be bigger than your delta H, okay? And exothermic reactions probably won't be. And then, yeah, you can read over essentially what we've, this is going to be like a kind of bookkeeping page. It talks about everything that we've talked about in this chapter of Tomail, okay, in terms of rates of reaction. Okay, so thanks for coming today. I'll see you guys on Wednesday, I guess. Or for those of you who are in lab, I'll see you later today. There's some, I have some more blank exam twos up here if anybody wants them, I don't know. Oh, and there should be a sign in sheet going around if you didn't sign in, make sure you do.


CHAPTER IX. INTO THE ENCLOSURE. In the torture chamber Dex wavered slowly back to consciousness to get the growing impression that he was being immersed in a bath of liquid fire. Burning intolerable pain assailed him with increasing intensity as his senses clarified. At last he groaned and opened his eyes, for the moment not knowing where he was nor how he had come to be there. He saw strange torture instruments and tall monstrosities with pumpkin-shaped heads surrounding him closely in a semi-circle, and staring at him out of great dull eyes. Remembrance came back with a rush, and he gathered his muscles to spring out the hateful figures. But he could not move. At waist and throat, at wrists and ankles, were hoops of metal.  Dully he wondered that he was still alive. His last recollection had been of the Rogan leader pointing his shock-tube full at him, his shapeless countenance working with murderous fury. However, alive he was, and most unenviably so. His hands, circumscribed to a few inches of movement by the bonds on his wrists, felt the smooth substance at his back, and with a thrill of horror he realized his position. He was crucified against the metal slab on which the slave had writhed in agony a short half hour ago. Again he strained and tugged vainly to get free.  The Rogan leader, squealing and grimacing, advanced toward the victim on the metal plate. One of the long arms went out and a sucker-desk was pressed to Dex's cheek. Dex quivered at the loathsome contact of that soft and slimy substance, then set his jaws to keep from groaning as the disc was jerked away, to carry with it a fragment of skin and flesh. Gingerly, the tall leader felt the twitching blackened stomp of his blasted arm. Dex grinned mirthlessly at that. He'd struck one or two blows in his own defense anyhow. At sight of the earthman's grin, an expression of defiance and grim joy that needed no interpreting to be understandable, the Rogan leader fairly danced with rage. His long arm went out to the switch beside the plate, and pulled it down another notch, just a little, not nearly to the current that had torn at the slave. At the increased torment resulting from that slight movement of the regulating lever, Dex yelled aloud in spite of all his will-power. It seemed as though his whole body were about to burst into self-generated flame. Every cell and fiber of him seemed on the verge of flying apart. He could feel his eyes start from his head, could feel every hair on his scalp stand up as though discharging electric sparks. A minute or two of that and he would go mad. He cried out again and twisted helplessly in his bonds, and then the terrible torture stopped. The Rogan had not touched the switch, yet whatever sort of current it was that charged the plate was abruptly clicked off, as though someone at a distance had cut a wire or thrown a master switch. Simultaneously with its ceasing, an invisible, crushing sea seemed to envelop everything. Dex felt his body sag against his mental bonds, as if it had been changed to lead. Before him the Rogans, who had been crowding closer to watch gloatingly each grimace he made, shot doorward as though their pipe-stem legs had been swept from under them. The leader fell on the stump of his seared arm, and a deafening squeal of rage and pain came from his little mouth. His tube fell from his grasp and rolled over the floor half a dozen yards away from him. Amazed, observing the stricken creatures only dimly through a haze of pain, Dex saw them struggle vainly to get up again, and heard them chattering excitedly to themselves. For the moment, in the face of this queer phenomenon, the prisoner seemed to be forgotten, and Dex was quick to seize the momentary advantage. Greca, he called, the tube! There on the floor! The girl raised her head quickly, and followed his imploring gaze. Laboriously she started for the tube. At the same instant the Rogan leader began to feel around him for his lost weapon. Not finding it, he raised his head and glanced about for it. He saw the girl making her way toward it, and, with a squeak of terror, began to crawl toward it himself. He was not quick enough. The girl, though not nearly as active under the increased pull of gravity as a person of earth might be, was yet more agile than the Rogans. And she was the faster mover in this tortuous, snail-like race. While the Rogan leader was still several feet away, she retrieved the shock tube.  With feminine horror of the thing that faced her, Greca hesitated an instant, a hesitation almost long enough to be fatal. Then, just as the Rogan leader was reaching savagely out for her, she leveled the tube at him and turned it to its full power. One last thin squeal came from the Rogan's mouth, a squeal that cracked abruptly at its height. What had been its gangling body drifted up in inky smoke. The others, called Dex, quick before they get their weapons! Greca swept the death-tube in a short arc in front of her, over the bodies of the remaining Rogans, as if spraying plants with a hose. One after another, toppling in swift succession like grotesque falling dominoes, the creature sagged to the floor and melted away. That one small part of Jupiter's red spot, at least, was cleared of Rogan population. Long shutters racked Greca's body, and her lips were a bloodless line in her pallid face. But she did not go into womanly hysterics or swoon at the slaughter it had been her lot to inflict. Moving as quickly as she could, she went to the metal slab and began, with shaking fingers, to undo the fastenings that held Dex prisoner. "'Good girl,' said Dex, patting her satiny bare shoulder as he stood free again. "'You're a sport and a gentleman. You don't understand the terms? They're earth words, Greca.  But let's get out of here before another gang comes and takes us again. Where can we hide?' "'I don't know any hiding places,' confessed Greca despairingly. The Rogan swarm everywhere. We will be seen the moment we try to leave here.' "'Well, we'll hunt for a hole anyway,' said Dex.' He assayed to walk. What with the tenancy of his muscles to jerk and collapse with the aftermath of the torture he had endured, and the sudden and inexplicable increase in gravity that bore him down, he made heavy going of it. "'First we'll go up and get brand.' "'Yes, yes,' said Greca, a soft glow in her clear blue eyes. Let us go quickly.' She started toward the door, panting with the effort of moving. But Dex halted an instant to stoop and pick up another of the tubes. "'We might as well have one of these apiece,' he said.  They made their way out of the torture laboratory and up the incline to the street level, and it was just as they reached this that the burden of gravity under which they staggered was lifted from their shoulders as quickly as it had descended on them. Dex raised his arms just in time to fend his body from a collision with the wall in front of him. "'Now what?' he exclaimed. Greca lifted her hand for silence, inclined her head, and listened intently. As she did so, Dex heard the same noise her quick ears had caught an instant before his, a distant pandemonium of ringing gongs and siren sheiks, and squealing cries of a multitude of agitated rogons. "'What, the devil?' began Dex. But again Greca raised her hand to silence him and listened once more. As she listened her sea-blue eyes grew wider and wider with horror. Then frantically she began to race down a long corridor away from the street door. Dex hastened to follow her.  "'This is not the way up to the room where Brand, your friend is not there,' she interrupted. She explained swiftly, distractedly. During the shouts of the rogons I learned that he got into the great dome building somehow, and then was driven into the pen of the—' Dex could not get the next term she used, but her telepathic message of the peril she mentioned formed in his mind clearly enough. "'He got a flashing brain-picture of a great high-walled yard with a monster in it, of the kind he had caught a close-range glimpse a short while before. Also he saw a blurred, tiny figure running from wall to wall that was Greca's imagining of Brand and his efforts to escape the enormous beast. "'Good heavens,' groaned Dex, penned in with one of the things they showed me while I was stretched out on the rack. "'Are you sure, Greca?' she nodded and tried to run faster. "'This way,' she gasped, turning down a passage to the left that ended in a massive metal door. This leads to the enclosure. Oh, if only we can be in time!' Her slim fingers tore at a massive bolt that secured the door. "'Here,' said Dex, wrenching it open for her. And they stepped out into thin sunlight, onto a hard surface of reddish ground that was crisscrossed with innumerable rounded furrows, like the tracks old-fashioned fifty passenger airplane wheels used to make on soft landing-fields. Greca shrieked and pointed to the far end of the enclosure. Down there, flattened against the wall of the dome building, was Brand, and waddling toward him with a tread that caused the ground to quiver was a mate to the hideous creature the Rogans had used to terrify Dex in the torture chamber. Dex leveled the tube he was carrying, swore, hid it frenziedly with his hand.  Oh, like that. There. See if that puts a sting in your hide!' The distant monster stopped its advance toward Brand. A raw white spot, as big as a dinner plate, leaped into being on one of its enormous hind legs. It whirled with an ear-splitting hiss to see what thing was causing such pain in its rear. The frightful head whipped back at the end of the long neck to nuzzle at the seared spot. Then the giant lizard turned toward Brand again. A second time Dex pressed the central coil that formed the handle of the tube, as Greca had showed him how to do. A second time the rays shot down the field to flick a chunk of flesh weighing many pounds from the monster's flank. And this time it definitely abandoned the quarry behind it. With a scream like the keening of a dozen steam-wistles, it charged back over its tracks toward the distant pygmies that were inflicting such exasperating punishment on it. Dex swept the tube before him in a short half-circle. A smoking gash appeared suddenly in the vast four quarters of the monster. It stopped abruptly, its clawed feet plowing along the ground with the force of its momentum. An instant it stood there. Then, with its head swinging from side to side and lowered so that its looped neck dragged on the reddish-dusty ground, it began to back away from the source of its hurt, bellowing and hissing its rage and bewilderment. Brand shouted Dex, this end! Run, while I hold the thing off! Brand began to race down the long enclosure ten feet to a leap. The great lizard darted after him, like a cat after an escaping mouse, but a flick of the tube sent it bellowing and screaming back to its corner. Dex gasped, Brand, thank God! For a moment he leaned, wide and shaken against the wall. Then Greca caught his hand in both of hers and Dex put his arm supportingly around his shoulder. They retreated back through the doorway behind them and slid the bolt across the metal door. End of Chapter 9 Chapter 10 of The Red Hell of Jupiter by Paul Ernst This LibriVox recording is in the public domain. The Red Hell of Jupiter. Chapter 10. The Tank Scheme Thank God you came when you did, repeated Brand. Then, with a moment in which, figuratively, to get his feet back on earth, the wonder of Dex's appearance struck him. How did you manage to get away? He asked. I was sure. I thought, when they dragged you out of the tower room, I wouldn't see you again. Rapidly, Dex gave an account of his ordeal in the torture chamber, telling Brand in a few words how he had attempted to win free of the Rogans, how he had almost succeeded, only to be caught again and clamped to the death-plate on the wall. But just as the big fellow was about to cook me for good and all, he concluded, something happened to the current and to the gravity at the same time. That was when I pulled the lever in the dome-building, exclaimed Brand. He told of what had befallen him in the Rogan powerhouse. That levered, Dex, he said swiftly. It's the keynote of the whole business. It absolutely controls the pull of gravity, and Lord knows what else besides. If we could only get at it again. Perhaps we could not only shut it off so that Jupiter's pull would function again, but also reverse the process so its gravity would be increased. Think what that would mean. Every Rogan in the red empire stretched out and immovable, possibly crushed in by his own weight. It's a wonderful thought, sighed Dex, while Grecoise glowed with a sudden hope for her enslaved race. But I don't see how we could ever! He stopped and glanced in alarm down the passage behind them. Grecoise and Brand, hearing the same soft noise whirled to look too. Far down the passage, just sneaking around the bend, was a group of Rogan guards, each armed with a death-tube. Back to the pen, cried Brand. He slid the bolt and jerked the door open. They rushed into the walled enclosure again, the slamming of the door behind them, cutting off the enraged squeals of the Rogans. This isn't going to mean anything but a short delay, I'm afraid, said Brand, clenching his fists in an agony of futility. They'll be in here in a minute and get us like trapped rats. Not before we get a lot of them, said Dex grimly. But that isn't enough, man. We don't want to die, no matter how decently we do it. We've won free and stayed free this long. Now, somehow, we've got to reach our ship and get back to earth to warn them of the danger that hides here for our planet. He strode tensely up and down, smacking his fist into his palm. The lever, he exclaimed. That lever! It's our only answer. If we could get to it. But how can we? We couldn't break into the dome, now the Rogans are on the watch for us, with anything less than a charge of explosives. Or a tank. God, how I'd like to have an old-fashioned fifty-ton army tank here now! Greka exclaimed aloud as Brand's fleeting mental picture of one of Earth's unwieldy, long-discarded war-tanks registered on her brain. There is the great beast there, she said, hesitantly, pointing a slim forefinger at the huge lizard that had backed into a far corner and was regarding them out of dull, savage eyes. Then she shook her head. But that is impossible, impossible! The men stared at her with the dawning realization in their minds. Then they gazed at each other. Of course, said Brand. Of course! Greka, you're marvellous! Wish we had a tank? Why, we've got one!  But it's not possible! replied Greka, her head dropping dejectedly. My people, as driven slaves, till the fields with great animals that were trapped in the surrounding jungles. They harness other great animals to haul burdens. But none of the beasts are like this one. This kind cannot be tamed or harnessed. It is too ferocious. It is used only as a scourge of fear to crush us into complete submission. Can't be tamed? Brand said. We'll see about that. Come on, Dex. Just a minute, said Dex. He flattened against the wall, motioning them to do the same. Then he leveled his tube at the door.  Dex pressed the release coil of his tube. Without a sound, the rogan slumped to the ground, a smoking cavity in its shoulders at the spot where its head had been set. In an instant the body too disappeared, an upward coiling wisp of black smoke marking its vanishing. Another rogan, tiptoeing out, met the same fate and another, and then the door was banged shut again and the bolt grounded to place on the inside. That'll teach him to be careful how he try to rush us from that door, said Dex through set teeth. Now let us see if that tank scheme of ours can be worked. He picked up a tube dropped by one of the rogans and handed it to Brand, showing him which coil to press to get full force as Greca had in turn informed him. Down the field, commanded Brand, we'll go about thirty yards apart and try to herd this brute back through the walls of the dome building. Once it's inside, we'll try to rush to the lever before the rogans can down us and jam the thing past its terminal peg and into reverse action. I don't know that there is a reverse to it, but we can try. Greca, dear, the girl started at the warmth of his thought and a faint pink rose to her pale cheeks. You'd better stay by my side.  Besides, you can keep your tube leveled at the doorway as we go and discourage any rogans who might pluck up courage to try coming out again. They started down the field toward the nightmare thing that snarled and hissed in its corner. On one side of the big enclosure walked Brand, with Greca close beside him, glancing continuously over her shoulder at the rear door and holding her tube in readiness to check any charge the rogans might attempt to make from the tower building. On the other side, keeping an equal pace, advanced decks. With tubes of death as whips and with death for themselves set as the stake for which they gambled, they went about their attempt to drive the brainless monster before them through the solid wall of the dome building. And there followed what was probably the strangest animal act the universe has ever witnessed. The first thing to do was to route the enormous lizard out of the corner where sullen fear had sent it squatting. Decks contrived to do that by standing next to the wall at its side and sending a searing raid that just touched the scaly, tremendously thick hide. The monster bellowed deafeningly and, with a spot smoking on its flank, waddled sideways to the center of the field. Its head and swaying long neck faced the earthmen, and its back was against the wall of the dome building. To that extent, at least, they had the creature placed, but they soon found that the struggle had only just begun. Bran got far enough around to focus his tube on the tip of a huge tail in an effort to swing the gigantic thing about. There was an unearthly shriek from the colossal beast and a foot and a half of its tail disappeared. Careful, called Decks, his jaw set and grim as the monster lashed out in its wrath. If you bore in too long with that tube, there'll be nothing left of our tank but a cloud of smoke.  Which, next instant, it did. With a whistling bellow, it gathered its tons of weight and thundered with incredible quickness at the gnats that were stinging its flanks and tail. Desperately, Bran played the tube across the vast chest, scoring a smoldering gash in the scale-covered flesh just above the gash Decks had seared a few moments before. Sorry, old fellow, Bran muttered to the screaming beast. We hate to bait you like this, but it has to be done. Come on now, do that wall behind you and give us a chance at the lever. But through the wall behind it the vast creature, not unnaturally, refused to go. It darted from side to side, backward and forward, up to the wall, only to back bewilderedly away from it, and constantly the tubes flicked their blistering, maddening rays along its monstrous sides and tail as the earthmen tried to guide it into the wall. Hope there's enough left of it to do the trick, said Bran, white-lipped. The monster was smoking in a dozen spots now, and several of the hump-like scales on its back had been burned away, till the vast spine looked like a giant saw that was missing a third of its teeth. God, I'm thinking we'll kill it before we can drive it through that wall. Greca nodded soberly, keeping her eyes on the distant door to their rear. Twice that door had been opened, and twice she had directed the death-rays into its opening to mow down the gangling figures behind it. But she had said nothing of this to her man. He was busy enough with his own task. The door to the dome, Dex shouted suddenly. But Bran merely nodded, even as a discharge from his tube annihilated the Rogan that had appeared in the doorway before them. He had seen that door stealthily opening even before Dex had. It had better be soon, Dex, he called.  Dex whirled in time to pick off a grotesque, pipe-like figure that had suddenly appeared on the broad wall of the enclosure. Then he turned to the frenzied problem of driving the monster through the building wall. The thing's going mad, Bran, he cried, his voice high-pitched and brittle. Watch out! It was only too evident that this statement was true. The baited monster, harried blindly this way and that, hounded against the blank wall behind it by something that bit chunks of living flesh out of its legs and sides, was losing whatever instinctive mental balance it ever had. Its dimly functioning brain, probably no larger than a walnut in that gigantic skull, ceased more and more to guide it. With a rasping screen that set the earthmen's teeth on edge, it charged for the wall on Dex's side. Dex just managed to swerve it with a blast from the tube so prolonged that half its great lower jaw fell away. At this the titanic thing went wholly, colossally mad. It whirled toward Bran, jerking around again as a searing on that side jarred its dull sensory nerves, then headed at last straight toward the stone wall of the dome building. With the rays from both tubes flicking it like monstrous spurs, it charged insanely toward the bulge of the circular wall. With all its tons and tons of weight it crashed against the stonework. There was a thunderous crackling noise and the wall sagged in perceptibly while the metal roof bent to accommodate the new curvature of its supporting beams. The monstrous lizard, jerked off its huge legs by the impact, staggered up and retreated toward the two men. But again the maddening pain in its hind quarters sent it careening toward the building wall. This time it raised high up on its hind legs in a blind effort to climb over it. God! It must be five stories tall! ejaculated Bran. Thunderingly its four legs came down on the edge of the roof. There was another deafening crash of stone and shrieking of torn metal. Just under the cornice the wall sagged away from the roof and the top rows of heavy stone blocks slithered inward. Again shouted Bran. His tube was pointing almost continuously now at the metal door leading from the dome building. The rogons inside, at the shocks that were battering down a section of their great building, were all trying to get out to the yard at once. In a stream they rushed for the doorway. And in loathsome heaps they fell at the impact of the ray and shriveled to nothingness on the bombarded threshold. Once more, Bran repeated, his voice hoarse and tense. And as though the monster heard and understood it rushed again with all its vast weight and force against the wall in a mad effort to escape the things that were blasting the living flesh from its colossal framework. This charge was the last. With a roaring crash a section of the building thirty yards across went back and down, leaving the massive roof to sag threateningly on its battered trusswork. It was as though the side of an ant-heap had been ripped away. Inside the domed building hundreds of rogons ran this way and that on their elongated legs, squealing in their staccato, high-pitched tongue. With blind fury the mad monster charged in through the gaping hole it had battered for itself. In all directions the rogons scattered. Then an authoritative tall figure with a tube in each of its four sucker-discs whipped out a command and pointed to the great coils which lay immediately in the berserk monster's path. The command restored some sort of order. Losing their fear of the beast in their greater fear of the damage it might do, the rogons massed to stop it before it could demolish the rogue heart of power. At this point Bran saw an opening of the kind he had been praying for. The rogons had retreated before the terrific charge of the monster in such a way that the space between its vast bulk and the control-board was clear. "'After me,' he shouted to Dex, "'one of us has got to reach that lever while the creature's still there to shield us.' The two earthmen dashed through the jagged hole in the wall and raced to the control-board just as the huge lizard, a smoky mass, sank to the floor. Bran gazed almost fearfully at the lever slot. Was there a reverse to the gravity-control action? There was room in the slot for the lever to be pulled down below the neutral point, if that meant anything. Behind them the great bulk of the dead lizard was disappearing with incredible quickness under the rays of the tubes directed on it. Now the pumpkin-shaped heads on the opposite side were visible through a fleeting glimpse of a skeleton that was like the framework of a skyscraper. And now the colossal bones themselves were melting, while over everything hung a pall of greasy black smoke. "'Hurry for God's sake,' gasped Dex. Bran threw down the lever till it stuck. At once that invisible ocean poured crushingly over them, throwing them to their knees and sweeping the rogons flat on their hideous faces, just as half a hundred tubes were flashing down to point at the earthmen. "'More if you can,' grated Dex, whirling this way in that and spraying the masked rogons with his death-dealing tube. Dozens went up in smoke under that discharge, but other dozens remained to raise themselves laboriously and slowly leveled their suddenly ponderous weapons at the earthmen. Bran said his jaw and threw all his weight on the lever. It bent a little, caught at the neutral point, and then jammed down an appreciable distance beyond it. Instantly the blue streamers that had stopped their humming progress from coil to coil with the movement of a switch to neutral, started again in reverse direction. And instantly the invisible ocean pressed down with appalling, devastating force. Greca and Bran and Dex were flattened to the floor as if by blankets of lead, and the scattered rogons about them ceased all movement whatever. "'Oh!' sobbed Greca, fighting for breath. "'Oh!' "'We can't stand this,' panted Dex. "'We fixed the rogons all right, but we fixed ourselves, too. That lever has to go up a bit.' Bran nodded, finding his head almost too heavy for his neck to move.  With a tremendous struggle he got to his knees beneath the master switch. There he found it impossible to raise his arms, but leaning back against the control board and so getting a little support he contrived to lift his body up enough to touch the downslanting lever with his head and move it back along its slot a fraction of an inch. The giant coils hummed a note lower, and some of the smashing weight was relieved. "'That does it, I think,' Bran panted, his voice husky with exhaustion and triumph. He began to crawl laboriously toward the nearest street exit. "'On our way,' he said vibrantly, "'to the spaceship. We leave for Earth at once.' "'Slowly, fighting the sagging weight of their bodies, the two earthmen inch their way to the street, helping Greca as they went. Among the sprawled forms of the rogons they crept, with great dull eyes rolling helplessly to observe their progress, and with feeble squeals of rage and fear and malediction following their slow path. On the street a strange and terrible sight met their eyes. Strune over the metal paving like wheat stalks crushed flat by a hurricane were thousands of rogons. Not a muscle of their pipe-like arms or legs could they move. But the gravity that crushed them rigidly to the ground did not quite hold motionless the shorter and more sturdily built slaves. Among the thousands of squealing, panting rogons that lay as though paralyzed on the metal paving crawled equal thousands of Greca's enslaved people, their eyes flamed with fanatic hate. And methodically, not knowing what had caused their loathed masters to be stricken helpless, and not caring as long as they were helpless, the slaves were seeking out the shock tubes that here and there had fallen from the clutch of rogan guards. Already many had found them, and everywhere gangling, slimy bodies were melting in oily black smoke that almost instantly vanished in thin air. As it was in the streets and in the great square in the center of which rested the earthmen's ship, just so they knew was it being repeated all over the Red Empire. Slowly crawling, fiercely exulting slaves were exterminating the tyrannous things that had held them so long in dreadful bondage. Before the sun should set on another flashing Jovian day there would be no rogan left in the Red Spot. And so it ends, said Brandt, with a great sigh. He moved over beside Greca and touched her lovely bare shoulders. They were shaking convulsively, though shoulders, and she had buried her face in her hands to keep from gazing at the ghastly carnage. Brandt pressed her to him. It's terrible, yes, but think what it means. The knell of all the rogans been sounded to-day. As soon as the secret of these death-tubes has been analyzed by our science and provided against, my friend and I will return from earth with a force that shall clear the universe of the slimy devils. Meanwhile your people are safe here, with the gravity what it is no rogan attacking hordes can land. They crawled torturously over the square to the spaceship. Brandt turned again to Greca, and now, in his eyes, was a look that needed no language of mind or tongue for its complete expression. Will you come to earth with me, Greca, and stay by my side till we return to set your people in power again?  My people need leaders now. I must stay and help direct them in their new freedom. But you, you'll come back with the others from earth. Try and stop him, Grindex, and try and stop me, too. From what I know now of the way they grow him on your satellite, his eyes rested on Greca's beauty with an admiration that turned her to rosy confusion. I'd say I'd found the ideal spot to settle down in. Brandt laughed. He's answered for me, too, and now a salute that is used on earth to express a promise. He kissed her, to her utter astonishment and perplexity, but to her dawning pleasure. Good-bye for a little while. The two earthmen hoisted themselves heavily over the sill of the control room of their ship and crawled inside. They secured the trapdoor and turned on the air rectifiers. Brandt moved to the controls, waved to Greca, who was smiling at him through the glass panel, and pointed the ship on its triumphant four hundred million mile journey home. The End of the Red Hell of Jupiter by Paul Ernst


Hi, well, I'm Stephen Nesheba, and I want to tell you a little bit about electron delocalization and resonance, and the set of ideas that I want to touch on here, listed here of the x, y, z pattern of the lone pairs and so forth, and to do that, I'll just, I mean, I have a number of examples to show you. So the x, y, z pattern, what does that mean? Well, what it means is I imagine that I have three atoms, there's a double bond between the first two and the third, it's got a single bond to it, but it has a lone pair of electrons, and whenever you see that x, y, z pattern, one thing that you can think is, oh, I could imagine another Lewis structure that involves those electrons coming down there forming a double bond, and those electrons in here leaving that double bond and forming a lone pair of electrons on x. And that's what I've drawn here, that lone pair of electrons, there they are, the electrons that form that extra bond, the pi bond between y and z is right there. So let's do some examples, here's o-zone, okay, does it satisfy the x, y, z pattern? Well, I think so, I've got a double bond here, single bond, and a third atom that's got a lone pair, it actually has three lone pairs, and so I can imagine now this pair of electrons coming down here, those pair of electrons leaving to form a lone pair, and here's that double bond. Now, a little bit about the nomenclature here, what we've drawn here are different resonance forms, okay, and so there's the word resonance, and the pair of electrons that came down off z to form the double bond, that's called the allelic lone pair of electrons. I have this phrase equivalent or unequivalent, what we have to decide here is do I have any reason to prefer this resonance form over that one, and the answer here is no, these oxidants are all identical to each other, so I would say these are equivalent resonance forms, okay, and when you have equivalence resonance forms, it means that I have to, in my mind, kind of think that reality is some average of those. That average gives rise to this idea of fractional bond order and partial charge, here's how it works. In this resonance form, I have a double bond, in this one I have a single bond, what's the truth? Well, it must be some sort of average, so I would say that the bond order between the first two oxidants is not one, not two, but one and a half, one and a half bond order, same thing here, one and a half. What about the charges? Well, I've drawn in the formal charges for you here, and both of these equivalent resonance forms, the central oxygen has a plus one charge, but notice here, there's a zero formal charge here, a minus one here, what's the average? Well, I would say the average must be minus and a half on that oxygen, same thing here, right, a minus one and a zero, so that must have a partial charge of minus and a half. So, whenever we have equivalent resonance forms, we typically get fractional bond orders and partial charges. One more thought here before I go into the next example, it's useful to think about how many electrons are delocalized, that is, how many are playing in this XYZ pattern. Well, it's kind of obvious here that there's those two that did that and then the two that left. So, we would say that the number of delocalized electrons in any XYZ pattern is two pairs, or, you know, there are four delocalized electrons that are, that ozone has, we would say, ozone has four delocalized electrons, pi electrons. Okay, how about NO2? Similar kind of story here, I have a double bond, single bond, and the third atom, the Z type atom has a lone pair, so I can do the same thing down they go, up you go, and so that lone pair is there now and that those electrons are not going to go, yeah, the second bond, the pi bond, partial charges looks like minus a half, plus one, minus a half again. Fractional bond orders, sure, I've got a bond order of two, bond order of one, the average two, one and a half. How about this one, this is CH3, C double bond O, CH2 with a net minus charge, and so I've got a lone pair of electrons on that carbon, and now I can say, oh yeah, that looks like a Z, down they go, up those electrons go to form now this oxygen with a minus one formal charge. This negative formal charge in that carbon has now gone away because it's formed a double bond. It's still XYZ, so we would still say that there are four de-localized electrons in this situation, but what the difference is that these are no longer equivalent residence forms. How do I know that? Well, in this case I have a formal charge of minus one on a carbon, in this case I have a formal minus charge on the oxygen, those are clearly not equivalent situations. However, we can also say when we have any equivalent residence forms, which one we like better, which one is predominant, and generally the way that we do that is we say, oh well, I think the more electronegative element oxygen will claim that minus one charge, so we generally prefer, we'd say this is a more predominant residence form. Okay, here's one last example. It doesn't satisfy the XYZ pattern, but there are still de-localized electrons. I just wanted to show you an example of this. So I have a carbon over here, okay, this is the allylic cation, it's called, and there's a, this carbon here doesn't even have a complete octet, and there's no lone pair floating around here, but this carbon could claim that pair of electrons by stealing it basically from that carbon, and that's what I've drawn here. Now this carbon has lost a pair of electrons, so it's got a plus one charge, and this carbon here has a complete octet, so it's happy. We have a similar thing that we would say, oh, the bond order must be one and a half, the partial charges must be plus a half, plus a half, and zero on that carbon. But the big difference now, of course, is that besides the fact that it's not XYZ de-localization, we also have just two de-localized electrons that are better at playing a role in that molecule. Okay.


Hello and welcome to this session. Today I will help you with the following question. The question says, how are prisms and cylinders alike? Let's move on to the solution. First let's see what a prism is. A prism is a polyhedron whose base and top are congruent polygons and whose lateral faces and holograms in shape. Let's see what a cylinder is. A cylinder is a three-dimensional figure similar to prism. At its bases are congruent circles state of polygons. Let's have a look at the figure. Now this is a cylinder. These are the two bases of the cylinder and this is the lateral face. Now this is a prism. These are the bases and these are the lateral faces. According to the definition of the prism the base and the top are congruent polygons and these lateral faces are parallelograms. And the cylinder is similar to the prism but the bases are in the circular shapes instead of polygons as in the prism. We can say that when the number of sides of base of a prism becomes larger and larger it becomes a cylinder. Therefore we say prism and cylinder will answer is a prism becomes a cylinder as the number of sides of its base becomes larger and larger. So hope you enjoyed the session. Have a good day.


small things that can tell you a lot about a person. One, their body language. From posture to facial expressions to hand gestures, researchers believe that our body language and nonverbal cues make up to over 65% of all communication. Two, their social media accounts. Their social media presence shows how connected they want to be, while their privacy setting shows how much they're comfortable sharing with people. The pictures they post or share tell you a lot about what they like, whether it's going out with friends, eating good food or watching movies. And the things they tweet about can give you a lot of insight into their likes, dislikes and opinions as well. Three, the way they dress. Those who dress casually are often laid back and easygoing people who value comfort over style and don't care much for impressing others.


An ideal regenerative Rankine cycle with a closed feedwater heater uses water as the working fluid. The turbine inlet is operated at 500 psi and 600 degrees Fahrenheit, and the condenser is maintained at 5 psi. Steam is supplied to the feedwater heater at 40 psi before being expanded into the condenser. Determine and complete the following. First, why the proportion of mass flow rate that leaves the turbine early to feed the closed feedwater heater, the specific work-in relative to the cycle as a whole, and the thermal efficiency. So note that in this problem, we still have the medium pressure occurring at 7 and 3 for the closed feedwater heater, but instead of compressing it up to the high pressure before mixing, we are expanding it down to the low pressure before mixing. That means that one pump is accomplishing all of the work and that one, two, five, and six all have the mass flow rates of the cycle. Let's start by identifying our independent intensive properties for the state points so that we can then determine the specific work-in, the specific Q-in, the specific work-out, and the specific Q-out, and then the thermal efficiency. I will start this process by pointing out that we still have three pressures, 500 psi, 5 psi, and 40 psi. Which state points have the high pressure? Two, five, and six. Which state points have the low pressure? Eight, four, and one. That leaves three and seven with the intermediate pressure. So I will populate one independent intensive property for all eight of our state points, using pressure. Next I will consider the pump and the turbine. I was given no indication as to an operational efficiency, so I will assume that they are both 100% efficient. That means that the process from one to two is assumed to be isentropic because an isentropic process represents the ideal work for a turbine and a pump. And then I assume that S7 and S8 are all equal to S6. That leaves me with state point one, three, four, five, and six. Left hanging. State six is easy. We have a temperature. So state six has a temperature of 600 degrees Fahrenheit. Next I'll assume that the condenser just condenses, and in this case is also a mixing chamber, but the condenser condenses, and as soon as the water has condensed, it leaves the condenser. It's just a mechanical device where water condenses and then it falls to the bottom and leaves. There's nothing to refrigerate it, to sub-cool it, to hyper-compress it. There is just a condensing process and then the water leaves, so we assume it leaves as a saturated liquid. Then three, four, and five. Well, I can make the same assumption about state three that I did in the previous problem where I had assumed based on the same concept of using latent energy for the heat exchange that the water that leaves at three has condensed and leaves. And then because I'm assuming that our closed feed water heater is operating ideally because I was given no indication otherwise, I'm going to use the same relationship for maximum conditions, which is a temperature at five being equal to a temperature at three. That leaves me with state point four. And to answer that question, let me pose a question. What do we know about expansion valves? Well, if we were to set up an energy balance on the expansion valve, I have no opportunities for heat transfer nor work. Therefore, this open system undergoing a steady process would have its energy balance simplified down to the sum in November theta is equal to the sum out of m dot theta, theta contains enthalpy, kinetic energy and potential energy. So if I neglect changes in kinetic and potential energy, I'm left with m dot three h three is equal to m dot four h four. And then if the mass flow rate at three has to equal state four, because it's a steady device with one inlet and one outlet, then h three must equal h four. Therefore, we treat expansion valves as being isenthalpic, that is, of a constant enthalpy. So I use x one and p one to look up s one, then I use s two and p two to look up h two. I guess I also look up h one using x one and p one. And I use x three and p three to look up h three and use h four being equal to h three to announce that h four is known. And then I use t five and p five to look up h five. So I have to go back to state three look up the saturation temperature corresponding to our 40 psi. Then I use t six and p six to look up h six and s six. And I use s six to look up h seven and h eight using the pressure at the medium pressure and the low pressure respectively. So I have everything I need to perform all eight enthalpy lookups. So let's just assume that we had them and move on. The next process would be to calculate the specific work in the specific queue in the specific workout and the specific queue out. The specific work in is going to be occurring in the one and only pump. Let me back up a second. We're defining y as the mass flow rate that leaves the turbine early. So I'm calling y m dot seven over m dot six. And then the remainder one minus y is m dot eight over m dot six. And I recognize that one two five and six are all the same. And they are all the mass flow rate through the cycle. Then eight stands alone. And seven three and four are all the same. So specific work into the cycle would be the total power input divided by m dot cycle, which would be m dot one times h two minus h one divided by m dot cycle because m dot one is equal to m dot cycle. That means my specific work in is just h two minus h one per queue in I'm looking at the boiler boiler also has the mass flow rate through the cycle flowing through it, which means that I'm just going to be left with h six minus h five. For our specific workout, we have the same exact energy balance that we have had for the previous two examples. So I'm going to use h six minus y h seven minus the quantity one minus y h eight. And if you want to see why unintended, you can go back and watch those videos again, h six minus y h seven minus the quantity one minus y h eight. And then and then specific you out is going to be the complicated one this time because I have multiple inlets and outlets. So let's just walk through that energy balance. I have entering mass flow rate at eight and four. Let me double check those state point numbers. And because I have a steady device that is an open system, my energy balance is going to simplify quite a bit. One to skip a few I can jump to writing q, as well as the sum in of m dot theta is equal to q dot out plus the sum out of m dot theta because there's no opportunities for heat transfer in nor work. And it's an open system operating steadily. And then theta contains enthalpy plus specific kinetic energy plus specific potential energy. So if we assume that changes in kinetic and potential energy are negligibly small, that means I'm left with the sum in of m dot h. There are two inlets so that would be m dot eight h eight plus m dot four h four is equal to q dot out plus m dot one h one, the one and only outlet. Therefore q dot out is going to be m dot eight h eight plus m dot four h four minus m dot one h one. And then if I divide everything by m dot cycle, I'm going to be left with m dot eight divided by m dot cycle which is one minus y plus m dot four divided by m dot cycle which is y minus y times h four minus m dot one divided by m dot cycle which is just one h one. So with these four equations, I can calculate my specific works and heat transfers. From that I can determine my network and that heat transfer and then thermal efficiency. All I need to do that are my eight enthalpies which you'll remember I totally know by now because I totally looked them up and y. So in order to be able to complete the problem, we are going to have to determine y. And remember in order to compute y, we have to perform an energy balance on a device about which we know everything. We can't analyze the boiler, the turbine, the condenser nor the pump because I don't know Q in, work out, Q out nor work in. The expansion valve is boring. There's not much to do there. Therefore I'm left with the energy balance on the closed feed water heater. So that energy balance is something that we've done before so I will go through it relatively quickly. So I'm going to have the sum in of m dot h is equal to the sum out of m dot h because there's no opportunities for heat transfer nor work and changes in kinetic and potential energy are negligibly small. So I'm going to write that as m dot two h two plus m dot seven h seven. That is equal to the sum out of m dot theta, which is going to be m dot five h five plus seven dot three h three. And then I'm going to group together my mass flow rates to limit how many y's I have to keep track of. So two and five will be together and that's increasing in energy. So I'm going to want to write that as m dot two times h five minus h two. That would be the right hand side of my equation. So I'm left with m dot seven times h seven minus h three five minus two seven minus three energy gained energy lost. That makes sense. Next I will divide everything by m dot cycle m dot two divided by m dot cycle is one because m dot two is equal to m dot six and m dot cycle and m dot six are the same. So note here that if you had just copied over the energy balance on the closed feed motor heater complete with all of the algebra below it from the previous problem, you would have an incorrect answer because the mass flow rates are different. Seven and three are both y here. So m dot seven divided by m dot cycle is just going to be y times h seven minus h three. Therefore, y is equal to h five minus h two divided by h seven minus h three. So at this point, all that's left to do to finish the question is look up our eight enthalpies, plug them into this relationship down here to determine why plug our enthalpies and our y values into these relationships to determine the work in the queue in the workout in the queue out and then compute a network out and a thermal efficiency. So again, because the property lookups are supposed to be something that you master in thermal one, it's a little bit outside the scope of thermal two for me to spend a whole bunch of time in this example problem video looking those properties up. So I'm just going to look them up and cut that out of this video. If you want to see where I got the numbers, I will include the work with this PDF so that you can follow it. That will be linked in the description below the video. But in the meantime, here we go, you ready? All eight enthalpies three, two, one. Now that we have all eight enthalpies calculating wise, just a matter of computing some numbers together. For that, we will use our calculator, wake up calculator. And I am going to take h five minus h two, which is 237.35 minus 133.27 divided by seven minus three, which is 1,085.02 minus 236.16. That yields 0.1226. Now we can take that number and plug it into our relationships for work in queue and work out in queue out. So I'm beginning with h two minus h one, which is 133.27 minus 130.17, which gives us 3.1. And then h six minus h five would be 1298.3 minus 237.35, giving me 1060.95. And then h six minus y times h seven. So 1298.3 minus y times h seven minus the quantity one minus y times h eight yields 328.078. And then one minus y times h eight, which is this quantity I already have, probably would have been faster just to start over. But here we are, one minus y times h eight plus y times h four, which was 236.16 minus h one, which is 130.17. And I get 735.972. And then from those quantities, I can determine a network out a net heat transfer in and a thermal efficiency. So 328 and change minus three and change yields 324.978. And then Q in minus Q out is the same number, which indicates that we built those equations correctly. And then we take that number, and we divide by Q in to yield thermal efficiency of 30.6%. So part a asked for y, part b asked for specific work in, and part c asked for thermal efficiency, which means that we are done with our calculations. What I would like to do next is probably unsurprising, like to plot this on a TS diagram. So state one is going to be here, low pressure, assumed to be a saturated liquid, then state two is directly above it, all the way on the high pressure side. You can draw that a little bit better. Also, let's switch to black. So it's easier to see. And two, and then from state two, we are gaining a little bit of heat before we get to state five. And state five was a compressed liquid. So I'm going to leave that in our compressed liquid region. I'm going to call that, oh, I don't know right about here. And then it goes all the way up to state six, which is our maximum temperature and pressure that we'll call right here. And then that expands down to seven and eight, which are directly below it. I believe seven and eight were both saturated liquid vapor mixtures and they are quality of 0.9 and 0.82. So my graph isn't perfectly to scale here, but hopefully it gets the point across. And then seven gives up some of its heat going to three, which is a saturated liquid. And then we have a line of constant enthalpy from three to four. Remember, those look like this. So encountering the low pressure line. And then that is meeting the process from eight to one. So we end up with process line like this. And that's our diagram.


Yes, Marcello. How are you? I'm good, how are you? We're here with fan-favorite centre-back Marcello. We're going to do a bit of Christmas shopping. It's a special edition. We're going to see what his swag's like. Stick around. You don't want to miss this one. Marcello, you've set it in pretty well at the club. What do you think has been the key to you settling in? I wonder. I reckon that everyone welcomes very well. That's really important. Every club I have a play, every country I have a being. So I give 100% of myself to get into the culture of the club. Also the country. I think that's the key. I feel like you've adapted to the West style. How we're a little bit gritty. I see you when you play.  Is that something you've just been throughout your whole career? Sure, sure. I grow up in an environment that's kind of favela. I would appreciate to come from that place. You've been doing amazing. We've got his family here as well. We're going to talk a little bit about your fashion style. I'm hearing from the powers of B that you're a bit of a golfer. Is that true? Good at golf? I'm really good at shooting. How long have you been playing for? For six years already. I'm expecting you to be good. I thought golf was not that long. Did you take lessons? Yeah, I take lessons. I was seven. Actually, I thought it was really good. Recent. I'm just having invested here. But we're getting there slowly. Does anyone else on the team play golf? Yeah, Mark Rusenterson, he plays golf. Pretty decent. He plays one hand cap. Daniel Magrush, he's also starting to play golf. So we have a couple of players. Lawrence also plays some time. Lawrence is really good. He's getting there. What kind of trainers are you into? I'm a really classic one actually. My wife is a specialist in fashion. She helps me a lot. She dresses you every time? Not every time, but she helps a lot. I think the trend now is a kind of quiet luxury. That's what I'm trying to wear right now. You could see that simple and effective. I like that. Shoes will be the same. Obviously we've got the family over here. Do you like the Jordans? Which Jordans are your favourite? One, fours. Fours? He likes the fours. He's got swag, you know? Actually he has a different style. He's more aggressive. More like it's out there. More colors and everything. What about your brother? What kind of shoes does your brother like? Jordans as well? No. What is it like? French, English and Portuguese. French, English and Portuguese? What? We lived for six years in France. They went to the French school as well. They played Fortnite with the French friends. What was your favourite country to live in? Here? Because of the sun. How old are you? Ten. Ten and thirteen. Jogo likes Moccasio. He's really a fan of Moccasio. Your favourite player, Neymar? What about you? You should say your dad, you know? No, they don't like him.  Of course. Ronaldo has a Messi. This is a big one. This is a big one. Come on, come on. One more, one more. Thank you. Is it comfortable? You're taking it? Great. How do you say it? Very perfect in Portuguese. Perfect. How do you say it? After you give something for you? Obrigado. Obrigado. Obrigado. Thank you. They're teaching me. We're rolling over to the men's clothing section with Marcelo and his wife, Tatiana. She's a stylist, I believe. We're going to allow her to style him today. Are you cool with picking out some stuff for him? Of course. What's his fashion like? He prefers white and black. You can sometimes wear a combination for the shoes. Which one did you say he liked? Which one? You would like for him? Maybe. Maybe a little bit of dark. And you like a shirt? If she said it's good, it's good. That's a great answer. Do you like it? And white shoes too? Yes. Shoes can be a little bit colored to break it a little bit. I'm trying to think. Maybe red. Maybe red. Maybe red. But white would also go really well with it. White would make it clean. Smooth. For your shoes. They have some accessories. What kind of watch are you into? I'm wearing a Louis Vuitton watch. The money is good. How's it been for you living in Australia with moving the kids and everything? It's a little bit hard because the children of course when they move them every time it's so hard to study for other languages. It's Australia. It's amazing. I don't know the countries you guys have lived in Holland. You live in France. Germany. Poland. Turkey. Which one do you like the best? I mean we enjoy every country we have been. Different time, different stage of our lives. I always say that we enjoy now. That's important. Now we enjoy a lot of Australia. You like the beach? Yes, the beach. We like to go around. Downtown city. What kind of accessories are you thinking? Do you like it? You got nice hair man. See that? Don't be. We're going to zoom in on that. Okay, let's go to the the hat section. It's for golf. It's for golf. Okay. This one will be fine. Just took him for that. No, that's different. You never can use a hat. At least you know it. You can't mix it. It's upside. That's true. The black hat. This is the Marcelo summer fit styled by his wife. Luxury. But you mix it with the Louis Vuitton watch. And it's good. Very, very good. I spoke to Borrello before and he said it's a very good team spirit. How do you feel about that? I feel the same. All the players are really nice. We understand each other. We spend a lot of time together. In the training session and outside of the beach as well. We go often to have a lunch. When you train here in the coming bank we go straight to the restaurant to have the time together. It's pretty good actually. One of the best group I ever had in my life. That's a big one. He's playing on some teams. Players are really honest with each other. That's what makes a good team.  Since we're talking about clothes who's the best dressed on the team? Borrello is really good. If you've been watching the videos he's been getting the tics. I have Nick also. Nick is a pretty good dresser. Good style. Anton is more classic as I am. He's from Sweden.  You have a couple of guys that like to dress different as well. No gold dress please. No gold dress? What's wrong with the gold? He prefers to dress like it's going to go. You don't like it? No no no please. So happy with everything we've got? Yeah we're happy. Kids are happy. You're happy? They're ready for Christmas. The wife dressed you. You're relaxed now. She knows what she's doing. Thank you so much. You're going to watch the game on Friday? Friday yeah. You're going to watch the games? Yeah good. They're going to score? Head up. Come on kids you've got to carry all this. Good. Good. Good luck ladies. See you later. Marcelo thank you so much for joining me. I really appreciate it. It was great to speak with you and hopefully it's all here man. Good luck.