The story you are about to hear is true. Only the names have been changed to protect the innocent. Fatima cigarettes, best of all long cigarettes, brings you drag net.  You're assigned to homicide detail. A woman has disappeared, taken from her home by a man posing as a police officer. Your job, find her. If you want a long cigarette, smoke the best of all long cigarettes. Smoke extra mild Fatima. Yes, Fatima is the king size cigarette which contains the finest Turkish and domestic tobaccos, superbly blended to make it extra mild. To give Fatima a much different, much better flavor and aroma than any other long cigarette. That's why Fatima has more than doubled its smokers coast to coast.  Best of all, long cigarettes. It's wise to smoke extra mild Fatima. It's wise to smoke extra mild Fatima. Drag net, the documented drama of an actual crime. For the next 30 minutes in cooperation with the Los Angeles Police Department, you will travel step by step on the side of the law through an actual case transcribed from official police files. From beginning to end, from crime to punishment, Drag net is the story of your police force in action. It was Tuesday, April 4th. It was warm in Los Angeles. We were working the night watch out of homicide detail. My partner's Ben Romero, the boss is Thad Brown, chief of detectives. My name's Friday. It was 10 minutes past 6 p.m. when I got to the basement of the city hall. Carpool. Thad Brown will be down in a minute. The captain will follow us out later. Okay. No contact yet? No, he's still waiting. You take care of the local broadcast. It's already going out. They'll put the descriptions on the air every hour. How's it look to you now? I don't know. Nothing more we can do to make a contact. Oh, here's Thad Brown now. You want to squeeze over a little? Oh, yeah, sure. Hi, chief. Hi. Let's go. Might as well take Beverly Boulevard, huh, Ben? It's as fast as any. You got the address there Friday? Yeah, it's 617 Paris Avenue. It's out by Echo Park. Who's covering the house now? Ross and Pachele are staked out in a private garage across the street from the house. Donahoe and Weisman are on duty inside the castle place. Want a smoke? Mmm, thanks. I'd mean one, wouldn't you, Joe? Yeah. You got the story from the maid at the castle's house, right? Mm-hmm. Check it out? Pretty sure she's telling it straight. If anything's wrong, I don't think she's got a hand in it. Hang on, Ben. You got the call about three this afternoon? A few minutes after, we went right out and talked to the maid. How'd she tell it? She said she was fixing dinner about two this afternoon when the doorbell rang. She answered it, and a young man in a gray suit asked for Mrs. Kessler by name. He told the maid it was an emergency. Well, the maid said Mrs. Kessler came to the door and the man identified himself as a police officer. Told Mrs. Kessler her husband had been hurt in an accident and she was to come right away. The man shows identification. The maid said no. Said Mrs. Kessler just took it for granted he was a cop. Yeah, go ahead. Mrs. Kessler got her coat and left with the man. About an hour later, her husband, Professor Kessler, got home. He wasn't hurt. He hadn't been in an accident. He hadn't seen his wife. As soon as he heard from the maid what had happened, he got on a phone and called her. What's the background of the husband, this Professor Kessler? He's supposed to have quite a name. He's a professor of philosophy out at Simmons College at a small school out in your Glendale. Oh, yeah. He's the vout man, president of one of the local synagogues. You sure about the maid's story, huh? Sure as we can be. She gave us a good description of the man who picked up Mrs. Kessler. I got it right here. Yeah. Here.  Six feet, 170 to 80 pounds. Gray suit, gray head, brown shoes. How about the car he used? Late modern Chevrolet. Dark blue, white sidewalls. That's all the maid could tell us. She didn't notice the last... You better cut over on the west like that. It'll take us past the beach or what? This Professor Kessler, see, he's been told what to do. Yeah, he's been briefed. We've had a couple of men with him since this thing broke. He's taken it pretty hard. How old a man is he? Oh, he was late 30s. Wouldn't you say so, Ben? Pretty close to 40. Nice for that old squad. Two kids in the family, just about school age. Boy and a girl. This next one ought to be Paris Avenue. Yeah.  Don't park too close to the house. I saw her do it right here, don't I say? What time you got? Man, 6.15. Most dark. Where's the garage I'm in a covering from? Can you see beyond that light pole there, the white stucco place? Oh, yeah. Next one here's a castle home. Doesn't look very rich. Neither do the kessels. I don't think they got much money. Hide down at home. Come in. Is that the husband? Yeah, I just got a phone call a couple of minutes ago. I listened on the extension. Who called? I tried to trace it. The guy wouldn't stay in the line longer. What'd you say? Tell the cops to stay away. I said it twice, tell the cops to stay away. Huh? I said if they don't, I'll kill her. The castle house had already been placed under strict surveillance and the victim's husband instructed not to contact the abductors without knowledge of the police. To the working detective, there's only one rule to go by when the job of solving an abduction is put in his hands. Find the victim as fast as possible, get the victim to safety, then go after the criminal. It's not an easy job. The responsibility is in the light and the outcome isn't always successful. If you press too hard, the abductor gets frightened and kills the victim. If you don't press hard enough, the criminal has more time to work for his pay-off and then escape. Somewhere between the two was the right answer. We had to find it. 6.30 p.m. Special details of men were ordered out to the bus depose the railroad terminals and the airports. Road blocks were set up at all main arteries leading into and out of the city. Every branch post office in Los Angeles was covered to watch for possible ransom notes addressed to Professor Kessel. 6.40 p.m. We met in the Kessel's living room. Chief Wiseman? Professor Kessel will be down in a minute. He says he's sorry to keep you waiting. You feeling any better? A little. Phone call about his wife shook him up a bit. How about those people who came in a few minutes ago? Were they? Relatives. Half a dozen of them. They're waiting back in the kitchen. How'd they know about Mrs. Kessel? They didn't. They'd been invited to dinner. They didn't know anything was wrong till they got here. Kessel asked them to stay for the meal. He wants to keep up appearances for the sake of his kids. He doesn't want them to worry about their mother. Is the dinner that important to him? Well, tonight's the start of the pesa when the Jewish religion pass over. Oh, yeah. It's one of the big holidays. Oh, I see. When they started off with this dinner tonight, is that the way? Yeah. Big dinner. They call them satyrs. Tonight they have the first satyr. Good evening. Sorry to keep you waiting. How are you? No, please, sit down. We don't like to intrude on your privacy, Professor Kessel, but I think you can see it's necessary. Oh, yes, of course. I'm very grateful. There's anything at all I can do to help. Do you have any idea who might be responsible for abducting your wife? That's what has me so confused. How do you mean to?  No, I don't know who it could be. How about the voice of the telephone professor? Did you recognize it at all? No, it didn't sound like anyone I knew. He talked so fast, I could hardly understand the man. Do you think the person who took your wife has some other motive besides holding her for ransom? I can't understand that either. If it's money they want, why go after a teacher's wife? $1,500 in the bank, that's all I have. That and this house. How about your immediate family, Professor? Well, my wife Ruth, her people, have quite a bit. I guess you would call them rich, but it's their money, not mine. I can't understand why anyone would do it. For Ruth, anything happened? Children? Albert? I'm sorry. It's all right, we understand. Albert? Yes, Bertha, come in, would you please? Gentlemen, this is my sister Bertha. She's here with her husband for the same. How are you? Albert, it's late. Son down, it's time to start the kitchen. Oh, yes. All right, Bertha, you tell everyone to come to the table, I'll be right in. The officers will have the first sater with them? Yes, Bertha, you please set them places. Yes, Albert. Say, we don't mean to intrude here, we can wait outside while you have your dinner. Oh, no, please. I'd be honored to have you sit at the table with us. Know what in the house should be without food tonight. First sater for Passover, it's the law. How's that thing? Oh, excuse me, the Hebrew law. Would you come this way please? Yes, Professor. He turned and let us down the hallway into the dining room. A long white cloth covered the table, and the center was a brightly polished brass candelabra holding four lighted tapers. There were a few platters of food already set out and at the head of the table where Professor Kessel stood an open prayer book. In order not to add to the alarm of his two small children in the absence of their mother, Professor Kessel introduced us his friends from Simmons College. This is Mr. Brown, Mr. Friday, Mr. Wiseman, Mr. Romero. You do, then. Of course. No, sit down, please, sit down. Yeah, it smells good. Yeah, you got enough room there, Joe. Oh, fine. Hey, how's it work, Wiseman? Should we join in the prayers? Not unless you speak Hebrew. Yeah. Yeah, telephone call. All right. Friday talking. This is Lacey, Joe. He just got a call from the morgue. Yeah? He brought in a body a few minutes ago. They checked the description. Yeah? They think it's Mrs. Kessel. I went back into the dining room and told Chief Brown about the call. He told Professor Kessel. He said he'd finish as quickly as possible so as not to alarm the children and then go with us to the morgue to check the identity of the body. The prayers continued along with the dinner. Yes, Papa. I'm sorry. Excuse me. I'm sorry. Excuse me. What was it, Wiseman? What was the boy saying? The ceremony during the meal. He's supposed to ask his father certain questions about the Passover and then the father answers him. I guess it was too much for Kessel. No broken leg. What did the boy ask him? Why is this night different from any other night? 7.30 p.m. Sergeant Wiseman and Donahoe stayed on duty at the house while Chief Brown, Ben and I drove Professor Kessel to the county morgue. On the way we called in and checked with Captain Steed of Homicide. He told us there had been no reports on Mrs. Kessel. 7.43 p.m. Ben and I took Kessel to the basement of the Hall of Justice, County morgue. This way, Professor. Oh, yes. You sure you feel up to it? Thank you. I'll be all right. Cold in here. Yes, sir. Hi, fellas. It's back here. Okay, Archie. This is Professor Kessel, Archie. I do. This way. Jane, door number five. I called over as soon as they brought it in. Yeah, thank you. This is the auto cam. No identification? No. Here we are. Thank God. Thank God. No, it's not my wife. It seemed as if both the victim and whoever had taken her had vanished completely. At 11.30 p.m. Captain Steed, Ben and I went across the street for a cup of coffee and a fried egg sandwich. We got back to the office at 10 minutes to midnight. Still no word. At 2 a.m. Ben and I drove back to the Kessel house to relieve Donahoe and Wiseman. There was no watch in the living room. In the bedroom directly above, we could hear Professor Kessel pacing the floor most of the night. At 5 a.m. Captain Steed called. He told us a letter addressed to the professor had been reported at the arcade post office. As soon as the outside of the envelope had been photographed and checked for prints, it would be brought out for Professor Kessel to open. Yeah, I'll get it. Chief. Good morning. Hi, Ali. Hi, Joe. In here. Did you lift anything off the envelope, Lee? Nothing we can use, no. Might have more luck with the letter. Good morning. You brought the letter? It's right here, Professor Kessel. I'd like you to stand by while we open it. This is Lieutenant Jones, my crime lawyer. Lieutenant? You check the note for fingerprints. Oh, yes, I can get you a letter open. I think this one over here. Yeah, that's all right. I could use my pocket knife. You want to grab one corner of the paper banner? Just the tip of the corner. Use your fingernail. Okay. And you have to open it and pin down these corners here. What is it for? The words are put together with small printed letters. They all seem to be the same kind of typeface. Letters were probably clipped from a book and pasted together to form these words. Who sent it? What does it say? Thanks, Lee.   Instructions follow in mail. No signature. 30,000. I haven't got the money. I can't get it.  But what can I do? I haven't got that much money. He says he'll kill her. What can we do? What we've been doing. Yes? Wait. You are listening to Dragnet, the case history of a police investigation presented in the public interest by Fatima Cigarettes. Fatima? The long cigarette that has more than doubled its smokers coast to coast. And there's a very good reason for this amazing increase. Men and women everywhere are finding out it's wise to smoke extra mild Fatima. I agree, says Lee Silver, news reporter. I agree, says Jean Mattson, airline stewardess. I agree, says Mike Charter, attorney at law. I agree, says Bob Beckwith, fashion stylist. Yes, all agree. It's wise to smoke extra mild Fatima.  The king size cigarette which contains the finest Turkish and domestic tobaccos superbly blended to make it extra mild. You will prefer Fatima's much different, much better flavor and aroma. You will agree. It's wise to smoke extra mild Fatima. It's wise to smoke extra mild Fatima. Best of all, long cigarettes. Wednesday, 7 a.m. With the aid of an iodine fume gun, Lee Jones checked the extortion letter for Mrs. Kessel's abductor for fingerprints and other marks of identification. He found nothing. The piece of paper on which the cut out printed letters had been pasted was of a common variety sold in most stationery in five and ten cent stores. Jones photographed both sides of the envelope in the letter. 11 a.m. Still no word. None of the special details had anything to report. At 1.45 p.m. another letter was delivered to the house. The envelope was open. The letter removed carefully and pinned down at the corners. It's put together the same as the last one. Tonight at 11 o'clock come along your car tell police I kill her. Is there more Friday? Yeah. Drive corner Lakeshore Charter Street. Wrap money brown paper. Small bills. Come along your car. Put package by fire plug then leave.  No signature. I haven't got the money. Lakeshore and Charter. That shouldn't be too hard for us to catch. Sounds pretty much like an amateur. That makes it touchy. If he's green he'll scare easy. If he's scared he may kill her. Not if we reach him. How can I get the money? You won't need any. We'll have a dummy package made up. There'll be a single dollar bill inside. This paper's cut to the size of currency. That's what you'll deliver. But when he gets the package when he finds out it's not the money what's he gonna think? We'll explain it to him. Starting at 10 o'clock that night more than a dozen cars from the detective bureau circled the area around Lakeshore Avenue and Charter Street keeping a distance ranging from three quarters to a full mile away so as not to scare off the abductor. Some of the cars were parked in service stations, some in private driveways. The neighborhood was located in the heart of a new veterans housing project for a full five blocks in either direction there were no buildings of any kind where we could keep an eye on the package of fake ransom money. The owner of one of the completed houses nearest the spot on Charter Street was contacted and he agreed to let us use his home as a lookout point for the stakeout that night. 9 p.m. Ben and I took up our positions on the roof of the lookout house. We were equipped with two pair of night binoculars and a walkie-talkie. I could think of a few other places I'd rather spend a night. How well can you see that intersection from here? It comes in fine with these binoculars. The guy shows we ought to see him. I better check with the captain again. What time you got? 9.25. Where's the skipper parked? Private driveway near Charter and Hayward. Friday to 105k. Friday to 105k. Come in. Got a clear view of the intersection. Nothing yet outside of cramped legs. You're reading me okay? Roger, standing by. If you're lucky, my kid can't see me now. Why? You'd never understand. Why should his father be sitting on top of somebody's roof late at night? You'd never get it. We waited. 10 o'clock came, 10.30. At exactly 11 p.m. as we watched through our night binoculars, we saw Professor Kessel drive up to the designated location five blocks away, placed the fake package of ransom money by the fire hydrant near the intersection and then drive away. 11.30, we waited. Midnight. 2 a.m., nothing happened.  Captain Steed checked with us periodically on the walkie-talkie. At 3.30 a.m., we were still waiting. At a few minutes past 6 a.m., Professor Kessel was directed to return to the intersection, pick up the package and drive back to his home. We were told to show maybe the suspected sense to trap, maybe he had no idea of showing up in the first place. Maybe Mrs. Kessel was dead, we didn't know. 10 a.m., Thursday, no further contact from the abductor. A special detail from homicide, including Ben and I were ordered on a door-to-door canvas of the general area around Lakeside Avenue and Charter Street. After seven hours of ringing doorbells and asking questions, we came across a Mr. Harold Olander, one of the longtime residents of the Silver Lake area. We showed him the general description of Mrs. Kessel's abductor. Yeah, that could be Thompson. I don't know for sure, though. Where did you see this Thompson, Mr. Olander? Oh, I saw him lots of times. He wrenched that cottage of mine down the street there. You see, the white one? Mm-hmm. Does this Thompson have a car? Thompson? Yeah, yeah, new one. I wonder if you could describe it. Chevrolet, nice-looking, blue color, I think. Could be, Joe. Is Thompson in the house now, Mr. Olander? He's been driving away already this morning. I can show you the house if it's official police business. It is. Come on, then. I got the key right here. The cottage is just down the block there. See the one I mean? The white one. Yes. How long's Thompson been in the house? Two weeks tomorrow. You noticed anything unusual about him? Mm-hmm. Nothing special. Comes and goes at odd hours. Then a lot of people do. I don't brag. The house right here. Does he usually keep all the blinds drawn? Yeah, another dimensionate. A lot of people do like this. Want to check back in the kitchen, Bannon? Yeah. Look at the living room, Sergeant. Yeah. On a stick of furniture. That's funny. You sure you didn't see anybody else in this house besides Thompson? No. No, he's the only one. Looks like it, Joe. Found this woman's purse stuffed in one of the kitchen cabinets. This sales slip was in the purse. This is Albert Kessel. There a phone here, Mr. Olander? Out in the hall. You still connected? Joe, I'll check back in the bedroom before you phone him. Right, Ben. No, you better stay with me, Mr. Olander, if you will. All right. Homicide. Do you have any idea where this Thompson is now, Mr. Olander? No. He comes and goes. I don't like the pride. This Friday, Skepper, we got one for you. I've got one for you. Mrs. Kessel, she's been found. Mrs. Kessel was unharmed. She had no idea where she had been or why she had been suddenly released. All additional information which she could furnish on the suspect was immediately relayed to the entire state and an APB. Two hours later, at a neighborhood garage Thompson patronized, we got his license numbered. We ran it through DMV and found the car was registered in the name of Charles Cottrell. 1015 Green Oak Drive, 7 p.m. Yes. Police officers, is Charles Cottrell here? Yes. Come in, please. I knew you'd find him. I kept hoping that I knew you'd find him. Where is he, ma'am? He'll give himself up. I'm his wife. I talked to him. There won't be any trouble. No trouble. Where is he? You've got to understand, he didn't know what he was doing. We needed money. He didn't know what he was doing. We'll have to search the house, ma'am. Charlie! All right, ma'am. Behind you back. You didn't know what you were doing. Tell him. We needed the money. I thought it would work. What would I do wrong? Come on. It should have worked. I planned it all out. Where did I make a mistake? When you thought of it. You just heard was true. Only the names were changed to protect the innocent. On August 2nd, trial was held in Superior Court, department 86, city and county of Los Angeles, in a moment the results of that trial. It's amazing how many long cigarette smokers are changing to extra mild Fatima. Here is the actual report. From coast to coast, extra mild Fatima has more than doubled its smokers. Yes, more and more smokers every day are discovering that Fatima is the king size cigarette that is extra mild. Extra mild because it contains the finest Turkish and domestic tobaccos superbly blended to make it extra mild. To give it a much different, much better flavor and aroma.  Best of all, long cigarettes. It's wise to smoke extra mild Fatima. It's wise to smoke extra mild Fatima. Charles Cattrell was tried and convicted of kidnapping and received the sentence as prescribed by law. He is now serving his term in the state penitentiary. You have just heard of Dragnet, a series of authentic cases from official files. Technical advice for Dragnet comes from the office of Chief of Police W.A. Wharton, Los Angeles Police Department. Fatima Cigarettes, the best of all long cigarettes has brought you Dragnet, transcribed from Los Angeles. Next here, Sarah Berner and Sarah's private caper on NBC.


We have a bunch of substances here, so to start off with we have helium gas in this in these balloons. This is coal. This right here is, this is salt or NaCl, sodium chloride. This over here is soil. This is a box of tin. This is a box of tin. Pure tin. This right here is water, H2O. And this is sand mixed with water. And you can think about which of these substances can be called as a pure substance and which of these can be called as a mixture. By the end of this video, we will be able to answer this question. We will be able to categorize many more substances under either pure or mixtures and to do that we should clearly understand the difference between these two. So let's begin. Now a pure substance can be either, can be either an element, can be an element or a compound. We know that elements can be metals, non-metals, even metalloids and compounds are formed when two or more elements join together. So for example, let's say we take, let's say we take helium gas. So this helium, it's a single element and because it's a single element, it can be called as a pure substance. It's a pure substance. This is helium right here. Now if we take water, H2O. Now over here, we can see that it is formed with two atoms, hydrogen and oxygen. So it's not really an element. When two or more elements combine, they form a compound. So H2O, H2O is really a compound. But still it's a pure substance. We can take more examples. So let's say we take salt, NaCl. Again, this is made up of two atoms, sodium and chlorine. Now this is also a pure substance. Not an element, but it's a compound, but still it's a pure substance. So NaCl comes right over here. Now a mixture is formed when elements are compounds or let's call them pure substances and pure substances mix with each other. So let's say we have, we have, let's say we have helium plus water. Let's say we have it in a beaker. Now this will be a mixture. This right here, it will be a mixture. Or if we look at the air around us. Now the air around us is made up of many gases. It has, it has nitrogen. It has oxygen, nitrogen, oxygen, some helium, some carbon dioxide. All of these gases, they make up the air around us. And therefore air is a mixture. These elements, these compounds, they are mixing with each other to form a mixture. Now let's take, let's take salt water. Let's take salt water. So salt water is really, it's really NaCl. It's sodium chloride, salt mixed with water. Now individually sodium chloride is a compound. It's a pure substance. Individually water is a pure substance. But when you, when you mix them, when two or more than two pure substances mix with each other, they form a mixture. So salt water that is NaCl plus H2O. This is a mixture. Now there is a major point of difference between pure substances and mixtures. That is pure substances, they have a fixed or a definite, fixed or a definite composition. And mixtures, mixtures, they have variable, variable composition. Composition. All right. What, what does that mean though? So let's take the example of salt water and understand what fixed and variable composition might mean. Now we can take five grams of salt. You can take five grams of salt and we can mix it with, you can mix it with 95 grams of water. So that will give us, that will give us really 5% salt solution. Or we can take, we can take 20 grams of salt and mix it with 80 grams of water. This will give us 20% salt solution. Now we can see that a mixture like salt water can have different, different compositions. There can be slightly less concentrated, like a 5% salt solution. There can be a highly concentrated salt solution, like a 20%. It can even go like 50%. So mixtures can have different or variable compositions. But within this particular solution, that is 5% salt solution, the salt is distributed uniformly. So we can call it uniform distribution, that is salt is distributed uniformly in this 5% salt solution. Similarly, salt is uniformly distributed in this 20% salt solution. So that really means if you have a salt solution, salt solution like this, you will have salt spread out throughout the body of the water, throughout the body of the water and showing salt with black, throughout the body of the water. NaCl is distributed evenly throughout the body of the, of the solvent, whatever the solvent is in this case, water. That is a uniform distribution. And mixtures can have uniform distribution. They can also have non-uniform distribution. So think of the image that you saw in the beginning, that was sand mixed with water, Now all the sand was settled at the bottom. It was not evenly distributed throughout the body of the water. That was non-uniform distribution. And mixtures can have two types, two types of distributions. Like I said, there is a name to that. Those mixtures that have a uniform distribution, they are called homogeneous mixtures. Homo gen OUS, I guess it's right, homogeneous mixtures. And then there is heterogeneous mixtures, heterogeneous mixtures, H-E-T-E-R-O heterogeneous mixtures. So homogeneous have uniform distribution, heterogeneous have non-uniform distribution, like chalk in water or sand in water. Homogeneous would be salt water or sugar in water, but both of them, they have variable composition. They have different composition, therefore they are mixtures. And you can see how they can have variable composition. Like you can have 10 grams sand in some water and you can add more sand in the same amount of water. So you have a variable composition, even for a heterogeneous mixture. Now if we come to pure substances, let's say we take a beaker and we take 10 ml of water. And we take one more beaker. We can take one more beaker. And then take, in that beaker we can have 50 ml of water. The only thing that we can change of pure substances is the amount that we take. We can take 10 ml, 50 ml, 1 liter. But in each case, the composition of water remains the same. This right here is 100% pure water. This right here is 100% pure water. Composition remains fixed no matter how much you take of that substance. Alright, so this is a major point that we can understand that is fixed and variable composition. Let's move on and talk more about how these two pure substances and mixtures, how they differ. So if we think about mixtures, if let's say we take salt water again, if we take salt water, we can separate it, we can separate it by physical means. We can separate it by physical means or physical methods. And pure substances can be separated by chemical methods. So what are some examples of these? Well for physical methods, you can think about evaporation, you can think about filtration, chromatography, crystallization, all of these are physical methods of separation. So let's say if you have, if you have some salt water in a crucible, you have some salt water and you can try and heat it, you can try and heat it from below. You can have a flame, you can heat it from below. After some time, all the water will really just get evaporated and all that will be left will be pure, pure salt, pure salt. So this is one way of separating a mixture and there can be, there can be filtration as well. So for example, if you have sand water, then you can filter out all the sand from that water. Again, that's a physical means of separation. Now for chemical, let's say if we have, if we have water, if you want to separate hydrogen and oxygen from water, we can't really have any of these physical methods do the work because if you vapor, if you heat water, it will just evaporate, right? So for separating water into hydrogen and oxygen, what we do is, we can take, we take, we take an electrolytic, electrolytic cell. So this one has, it has two electrodes. You can have both of the electrodes of graphite and they are connected to a cell or a battery. And then you have an electrolyte. You have an electrolyte. It's mostly water. So it's mostly water and also some sodium chloride is also some, some sodium chloride is also present in it and it also has water. Now, if when the current is passed through this, through the circuit, what starts happening is water starts breaking down into hydrogen and oxygen. So you start seeing hydrogen gas bubbles in one of the electrodes and oxygen gas bubbles in the other electrode. Now this is a chemical means of separation and that's how compounds can be separated or they can be broken down into their elements. But for doing that, you need to have a chemical means of separation. So this is one more difference between pure substances and mixtures that is the constituents or things that make up a compound. They can only be separated by chemical means and the constituents or the things that make up a mixture can be separated by physical means like evaporation, crystallization, filtration, sedimentation. All right, let's look at one last difference. So one last difference that really is that pure substances and we can think of compounds like water, sodium chloride or carbon dioxide. We can write compounds have different properties, different properties from their constituents. So this is really a fancy word but what it really means is anything that makes up a compound. So hydrogen and oxygen makes up water, right? So hydrogen and oxygen would be constituents of water. Compounds have different properties from their constituents but mixtures have the same properties as their constituents. All right, what does this mean now? Let's take the example of air in this case for mixtures. So if we take the example of air, we know that air is made up of nitrogen, there is oxygen, there is carbon dioxide, there is helium and if we look at the properties of air, all the properties that air shows are the same properties that these gases have. So for example, you can light up a matchstick in air and that is because oxygen supports combustion. If you remove oxygen and just look at it individually, even then it will support combustion. Each gas in this mixture really retains its own properties. We can take one more example, we can think about salt water. Again, if you look at this mixture of salt water, salt and water, they retain their properties even when they are mixed. And what are the properties of salt really? Well, you can think about how it tastes or when it starts melting. So if you look at salt apart from water, it will melt at a certain temperature. It's very high. If you mix it with water, it will still melt at that temperature, whatever that temperature is. So salt and water, both of them, they really retain their properties when they are mixed. So mixtures, they have the same properties as their constituents. But if we look at compounds, for example, let's say we look at water. Now, water has very, very different properties from its constituents, that is hydrogen and oxygen. Hydrogen and oxygen are gases at room temperature, but water is a liquid. Also, oxygen supports combustion. It helps things burn. But water, you know, it's the opposite effect, right? So compounds, they have different properties from their constituents. We can take one more example, we can think about carbon dioxide.  It says oxygen. Carbon is solid at room temperature. It can exist in the form of graphite, diamond. And oxygen is a gas at room temperature. So again, the properties of constituents are different from the properties of the compound, that is carbon dioxide. Carbon dioxide is used in fire extinguishers, prevents fire, it extinguishes fire. And oxygen, it helps burning, it supports combustion. So drastically different properties. And that is why we say that compounds have different properties from the constituents. All right, so let's summarize the differences now. Let me, let me write them over here. So this is pure substances and mixtures. Now the first difference is that pure substances are, they are really elements and compounds, single atom or atoms combined to form a compound. Mixtures are really formed when elements and compounds mix together. So formed due to mixing of elements and compounds. And when they mix, no new substances formed really, right? Air is not a new substance. It's just a mixture of many different things. But when elements like hydrogen and oxygen combine, they form something new. They form water. And that's a compound. Now the second difference is that they have a fixed composition. And mixtures, they have a variable composition. It doesn't matter how much of an element or a compound you take, the composition will be fixed. It doesn't change. But a mixture like, for example, salt water can have different compositions. It can be a 5% salt solution, 20%, 30% salt solution. It can have different composition. But within that one solution for salt water, it will be uniformly distributed. So such mixtures are formed, are called homogenous mixtures. So that is when the distribution is uniform. But that is not true for all types of mixtures. If we have sand water, then they're not really uniformly distributed, right? It's a non-uniform distribution. So even mixtures can have some types that is homogenous and heterogeneous. But both of them, both of them, they have variable composition. And you can understand that and you can understand that by looking at a salt water example in this video. All right. The third difference, the third difference is that pure substances show different properties from its constituents. And mixtures, they show the same properties. The last difference is that mixtures can be separated by physical means, evaporation, crystallization, chromatography. And for pure substances, you need to have chemical means of separation. To break down compounds, you need to have chemical means of separation. But to separate air into its constituent particles, you can have physical means. To separate salt water into salt and water individually, you can have physical means. So these are the differences between pure substances and mixtures. Now if we go back to this list of substances, we can try and categorize them under pure and mixtures, pure substances and mixtures. So helium, that's a pure substance. Coal is really a mixture, mixture of many, many hydrocarbons, compounds that are formed from hydrogen and carbon. And you will learn more about coal later in your courses in chemistry. Sodium chloride is a compound. Soil again is a mixture of many different things, many different types of compounds and elements. Pure tin, it's a metal, it's a pure substance. Water is a pure substance, it's a compound. Sand mixed in water, this is a mixture, right? It has a variable composition. You can have many, you can have a lot of sand in the same amount of water. You can have very little sand in the same amount of water. It has a variable composition. You can also separate it by filtration or sedimentation, physical means of separation. So sand water is a mixture.


Hey guys, I just wanted to make this video to show something I got in the mail today. I thought you guys might find this a bit interesting and a bit cool. So actually, recently at anime expo they announced that Yuji Hori, the creator of Dragon Quest, the original creator and writer and the game designer for Dragon Quest is going to be showing up to anime expo for a two day autograph session. So this is actually the first time he's come to United States for an autographing session in a very long time since Dragon Quest 9 came out like eight years ago. So it's been a really long time since he's been in the States so it's a pretty big deal. Unfortunately I wasn't able to go to anime expo this year because I didn't plan it out ahead. They announced that Yuji Hori was coming to anime expo very last minute which was kind of surprised to be honest. So by then it was too late to really go to anime expo to take the plane to Los Angeles. I'm actually from the east coast, I'm from the east coast and LA is all across the country so it would have taken a while. So I actually know somebody who was going to anime expo and I managed to get them to hook me up with Yuji Hori's autograph. So we're going to take a look at that but first we're going to take a look at the poster that they gave away. So they had a big Dragon Quest 11 sort of stand going on there.  Unfortunately I don't have the t-shirt but I did get this poster so let's take a quick look at this. So it got a little bit banged up inside the mail but that's the Japanese cover art for Dragon Quest 11. So you can see it right there and it's pretty, it's pretty rolled up there. So yeah that's pretty nice actually. The Dragon Quest 11. And if you flip it around to the other side you get the United States you know what localization cover art which is also pretty nice. It looks like in-game graphics kind of, it's also shaded so we have all the characters and everything and that's pretty cool as well. If you ask me though I actually like this cover art a little bit better because it looks more like the Dragon Quest games. The game cover art like 8, 9, 5, all the DS games. They all had us just you know Toriyama art cover art like this. So I thought that was pretty cool also I got that as a little bonus. But now we're on to the real, the real deal. So here it is. That is Yuji Hori's autograph. As you can see he wrote down the date and he signed it and he wrote drew a little slime there. He actually drew that. I also have a photo of him holding it but we'll take a look at that later. So yeah it's pretty nice. It's like a little card right? It's not a piece of paper. It's kind of a little bit smaller than Leris High's. And as you can see the card has all the characters on the bottom. There's the little slime, there's his autograph right there. Dragon Quest XI. It's kind of shiny you see. It's a nice cardboard sort of thing and it's in great condition. And also right here there is, let's see. This is the ticket to get the autograph. So it was stamped when it was autographed and on the back says Dragon Quest XI coming to PS4 and Steam on September 4th, 2018. And there's some social media links there. It's pretty nice. And yeah so they stamped it. This was for the Saturday 10th 30th to 11th 30th AM signing. It says here redeemed his ticket. His ticket number is 65. So basically Yuji Hori was signing Square Enix said that you should not bring any stored personal items because you won't sign that. But actually that was not true because Yuji Hori was signing pretty much anything people wanted to sign. He was signing people's games, he was signing people's shirts, people's other, the Anime Expo guidebook, all that stuff. So he was being pretty cool about it. He's a pretty cool dude. So yeah this is a really big deal for me. Dragon Quest is actually my favorite game franchise of all time. I grew up with it. As a kid I played all the games and I'm like obsessed with the Dragon Quest series and I've always wanted to meet Yuji Hori but I guess it just wasn't time. So maybe some other time. But for now having his autograph is good enough for me. It would be cool to meet him. But yeah he's an extremely influential figure in the gaming industry. He basically created what is the Japanese gaming industry today. He created Dragon Quest, he created Portopia, Serial Murders which basically kick-started about the visual novel genre and the RPG genre. So basically gaming would not be the same as it is today without this man. And I sort of have a really nice piece here and this is really great for my Dragon Quest collection you know. This is going to be a very important piece. So you know what I kind of want to do is I want to get this framed actually. I'm going to get a nice frame for this obviously because this is a really great treasure to have Yuji Hori's autograph.  That's kind of my plan right now. So yeah I think that'll be a really nice item to have. Because like I said he never does autograph sessions this man. Yuji Hori did one autograph session inside, he came to Manhattan back when Dragon Quest 9 was coming out. He did an autograph session at the Nintendo store. I don't remember, I don't think he's ever done one in Japan to be honest which is kind of interesting. He's only done signings in the United States. He did like one signing for Dragon Quest 6 at a random GameStop in LA which I thought was kind of interesting. And he did this one at an Anime Expo and it's been a while. So having his autograph it's not only rare but it's also very significant because he's a very significant person in the industry. And it's just great to have this. I'm really happy I managed to get this. I was really bummed out at first because I thought I wouldn't be able to make it and you know I'd miss out on this but luckily I found someone who was willing to grab me the autograph and they really pulled through it and looked at the tickets in great condition. This will be just great. The poster was a little bit banged up but you know the poster is not as... The poster was just a nice bonus. I'll hang this up somewhere. Maybe I'll get a frame but maybe this will go in my dorm when I move out. Yeah, there's the poster again. It's a nice poster too. It's a little bit smaller than it might look. That's about how big it is compared to this thing so it's like 11 by 17 inches sort of. And it's got a nice heart too but the real treasure here is UG Horizontograph which it's just great to have. And on the back there's not really anything. You see it's just kind of blank. There's a little bit of a stamp there. I don't know what that is. I was sure. But other than that it's great. Wow. And he even drew slime. See he must have been sitting there just drawing slimes and autographing for hours but I think he likes it a lot. He enjoys it. Meeting his fans and everything. I've also been keeping up with a lot of people on Twitter who have been meeting him and kind of checking out their autographs so it's just really great to have something like this. And I hope you guys enjoyed checking this out and seeing his autograph. This is a pretty rare item. I never saw this on eBay or anything after the anime expo was over so I can't imagine how hard to come by this might be. This is a pretty great item to have. So anyway thanks for watching. Hope you guys enjoyed the video and I'll see you next time. Bye.


Hello, I'm Ann McKenzie and I work as the head of the Consumer and Community Health Research Network here in Perth, Western Australia. We've been working with health consumers over the past 15 years to raise awareness of the linked data capability and the benefits of using linked data research. And I'm going to talk to you about how we've seen a real shift in attitudes from people being nervous and concerned about their risk to privacy to moving to a point now where people say have good governance in place, don't hide behind privacy issues and use the data that you have to make a difference to health outcomes for everybody.