Monday, October 4, 2010

Rutherford's Gold Foil Experiment

Have you ever wanted to prove your teacher wrong?  This was actually NOT the intention of Ernest Rutherford when he accidentally proved his teacher and mentor wrong.  Rutherford, a New Zealand native, had spent many a year as a student of J.J. Thomson and fully believed his "plum pudding" theory about the atomic structure.  In this theory, all particles in the atom were evenly distributed like plum pudding.  The image below shows this diagram.
To prove his teachers theory, Rutherford set up an experiment.  First, he set up a source of alpha particles that emitted them in a beam.  Rutherford also discovered these alpha particles which are basically high speed, positively charged, helium nuclie.  He then shot these particles at a thin piece of gold foil which was surrounded by Fluorescent screen that would detect the alpha particles.  The set up looked something like this.

What Rutherford expected, and what would prove Thomson's theory would be the alpha particles passing through the gold foil (made up of plum pudding molecules right? phhhht! noooo) with little or no    reflections.  What he discovered, however, was that the positively charged alpha particles would every so often hit something in the gold foil that made them bounce in huge reflections!  What they were hitting is the positively charged nucleus of the atoms in the foil.  To understand this more try this interactive activity on this link.  Watch how the more alpha particles that are introduced, the more are reflected from the nuclei.
Interactive Activity
You may be asking yourself, "Why does this matter?"  This is actually one of the most important moments in the history of SCIENCE!  This is the event that caused Rutherford to come up with a new model for the atom.  Without the gold foil experiment we might still be thinking we're connected by plum pudding like atoms.  Rutherford is the father of the modern atomic structure and this experiment helped start it all.
by: Paxton Swisher
Works Cited 
“About Rutherford’s Gold Foil Experiment.” eHow. N.p., n.d. Web. 3 Oct. 2010. <‌about_4569065_rutherfords-gold-foil-experiment.html>.
The Encyclopedia of Science. N.p., n.d. Web. 3 Oct. 2010. <‌encyclopedia/‌R/‌Rutherfords_experiment_and_atomic_model.html>.
kem korner. N.p., n.d. Web. 3 Oct. 2010. <‌2010/‌07/‌rutherfords-gold-foil-experiment.html>.
Molecular Expressions. N.p., n.d. Web. 3 Oct. 2010. <‌electromag/‌java/‌rutherford/>.
reich-chemistry. N.p., n.d. Web. 3 Oct. 2010. <‌stephen.gasecki.timothy.graham.atomichistory.fall.2009>.


  1. I really enjoyed reading your blog! I like how you talked about the experiment and Rutherford with jokes. The jokes kept my attention. The animation was very helpful too. I understand more clearly now how the experiment worked. You could have added more information about how Rutherford decided on creating his experiment with gold foil. Great job on your blog!

  2. Well done, but I have some suggestions:
    1. There were some basic spelling mistakes, along with some grammar ones, too. I think that these should be the least of your problems, but it would be in your best interest to fix them up and proofread.
    2. You need to understand the differences between the word "reflection" and "deflection." This error was critical in the understanding of the experiment, and it definitely needs to be fixed.
    3. I wasn't able to understand your references to plum pudding as being a type of atom, in and of itself. If you could clarify sentences such as the one regarding how we're not all made up of plum pudding, that would be great.
    4. My final suggestion is regarding the blog posting itself. Next time, take the creative license to use a digital tool. There were very few pictures and not even a single video used in the blog. Moreover, I wouldn't consider this an in depth explanation of the topic. It seems to me that you were just restating what we learned in class. Also, avoid doing the bare minimum, as I noticed you only had five sources and the posting itself was very short. Put forth all of your effort to really make an outstanding product.
    All in all, good job!

  3. Great job. You really found a good amount of information on this subjrct. you explained everything so well, and your jokes kept my attention.