yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Thomson's Plum Pudding Model of the Atom


2m read
·Nov 10, 2024

So the word atom means uncuttable, so the Greeks were thinking of it as a tiny hard sphere.

Phil: That's right.

Derek: And even up until the eighteen hundreds, that was the idea of an atom, the smallest piece of matter, a tiny hard sphere. But then we find out that that's not quite right, not quite. There were experiments in the eighteen hundreds that discovered the electron. JJ Thomson's experiments really worked out the electron was smaller than an atom, about 1000 times smaller than a hydrogen atom, and it was in all atoms.

Phil: That's right, not just hydrogen.

Derek: Whatever material he did his experiments on, he found there were electrons in them. There are electrons in all atoms. So I guess when you find something smaller than an atom, you need to propose a new model for the atom that actually has something smaller in it, some substructure.

Phil: That's right. So something like this. This is our model of the atom.

Phil: This is our model of the atom - in his day, it was known as the plum pudding model, but uh... here we have cherry tart.

Phil: Cherry tart, ok. So the idea being that we have an overall atom, usually pictured as spherical rather than 2D, but uh... but imbedded within it – and this is the important part – there are negative electrons represented by cherries, and they can come out. The overall atom is neutral, so that means that pudding part must be positive.

Derek: Now how would you get one of these electrons out of our pudding here? So electrons are negatively charged, so we'll need to put something very positive, which attracts electrons – a high voltage.

Derek: And that would have the effect of, say, like plucking a cherry out of the pudding.

Phil: That's pretty much it, yeah. You could do it kind of like that, so we're simulating what it would be like to put a positive charge up here.

Phil: That's right, that's right.

Derek: Pulling the electrons out of the atom, that's quite delicious.

Phil: Yeah! Well, that is the most delicious model of the atom, I've gotta say. So shall we uh, split the atom? Why don't you go ahead?

Phil: You want me to do it?

Derek: Yes! Who knows what could happen; a whole bunch of energy could be released.

Phil: Yeah, one, two, three...

More Articles

View All
A Meeting with the President | Genius: MLK/X | National Geographic
Look, either we’ve been summoned here so he can pressure us to accept watered down amendments to Kennedy’s civil rights bill, if the bill still exists. Whatever it is, we need to hear him out, because like it or not, whoever occupies that office holds the…
Dividing a decimal by a whole number on the number line
In this video, we’re going to try to figure out what 0.6, or 6 tenths, divided by 2 is. I’ll give you a little bit of a hint; we have 6 tenths plotted on the number line right over here. One way to think about it is if I wanted to go from zero to six ten…
Fishing Tips: How to Modify Your Rig for Rough Seas | Wicked Tuna: Outer Banks
My name is Britton, shocking for non-accountants, and owner of The Doghouse. I’m gonna show you one of the things that we do when we’re trolling in rough weather. Here on the Outer Banks, it’s notorious for windy conditions. Patrolling is a big part of w…
Median in a histogram | Summarizing quantitative data | AP Statistics | Khan Academy
Miguel tracked how much sleep he got for 50 consecutive days and made a histogram of the results. Which interval contains the median sleep amount? So, they’re saying, is it this interval on the histogram from 6 to 6.5, or this one, or this one, or any of …
Unreplaceable Skills: AI's Limits
Yesterday we talked about 10 skills that are now almost useless thanks to the rise of AI. Now, it’s only natural to talk about what particular skills an AI could never replace. These are the skills that even the most advanced robot cannot replicate, and p…
Methods for preparing buffers | Acids and bases | AP Chemistry | Khan Academy
Let’s look at two different methods for preparing buffer solutions. In the first method, we’re going to add an aqueous solution of a strong base, sodium hydroxide, to an aqueous solution of a weak acid, acetic acid. Our goal is to calculate the pH of the…