Why was JJ Thompson's 'Plum Pudding' model replaced by Rutherford's Nuclear model?

  • 0 votes

Thanks :)

Posted Fri 4th January, 2013 @ 11:04 by :) PurpleJaguar (: - Team GR

13 Answers

  • 4 votes

The Gold Foil experiment that was carried out by Rutherford, Geiger and Mardsen showed that there was something in the atoms of gold that was positively charged and heavy. This was called the nucleus and it was known to have a + charge. this disproved Thomson's model that the positive in the atom was like jelly. The gold foil experiment also showed that most of the atom was empty space - which again disproved Thomson's model because Thomson's model had no empty space. Therefore Rutherford came up with a new model, where the nucleus was in the centre (they didnt know about neutrons at this time) and the electrons were in the space surrounding it. rutherford's experiment disproved thomson's model which is why it was replaced.

Hope this helps : )

Answered Fri 4th January, 2013 @ 14:17 by Tilly - Team GR
  • 2 votes

Well in the exam you should probably say the following things (say it's a 4 or 5 mark Q):

1. Rutherford, Mardsen and Geiger completed the Gold Foil Experiment where they fired alpha particles at a thin sheet of gold.

2. They observed that the alpha particles using passed through, but some repelled and came back.

3. This showed them that most of the atoms were empty space, but that there was a heavy dense centre, which had a positive charge (because it repelled the + alpha particles).

4. Therefore the positive charge was not ' positively charged jelly' but a small centre of the atom, which hardly took up any space. 

5. This also showed that the electrons were not embedded in the 'jelly' but in the space around the positive nucleus. This hence disproved Thomson's plum pudding model and replaced it with Rutherford's nuclear model.

This should be good enough. For a 3 or 2 mark Q you can shorten it but as long as you mention the gold foil experiment, with the alpha particles and that this experiment showed that Thomson's model was wrong - then you should be fine.

Answered Sat 5th January, 2013 @ 13:44 by Tilly - Team GR
  • 1 vote

Do you need me to explain it anymore so that you understand it better?

Answered Sat 5th January, 2013 @ 09:31 by Tilly - Team GR
  • 0 votes

I kinda get it now 

Thanks :)

Answered Fri 4th January, 2013 @ 17:02 by :) PurpleJaguar (: - Team GR
  • 0 votes

No its okay, thankyou :)

If i was to write what you put, in an exam would i gain full marks?

My teach has not taught me this, and it says in the specification 'explain how results from the rutherford experiment led to the plum pudding model being replacedby the nuclear model' so im not really sure how to anwer a question about ths!?

sorry :P

Answered Sat 5th January, 2013 @ 12:59 by :) PurpleJaguar (: - Team GR
  • 0 votes

Thankyou so much for this :):):)

You're really good at physics! 

Answered Sat 5th January, 2013 @ 15:45 by :) PurpleJaguar (: - Team GR
  • 0 votes

Thanks. I did this last year, but I still remember it now because I found that part of the course really interesting. Though I was like you because my teacher didn't teach me any of it. I taught myself most of the physics and biology course last year.

Answered Sat 5th January, 2013 @ 16:22 by Tilly - Team GR
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I'm trying to teach myself all of the radioactivty and nuclear stuff :/

Answered Sat 5th January, 2013 @ 16:36 by :) PurpleJaguar (: - Team GR
  • 0 votes

That's why I have been asking so many questions on it :/ :P 

Answered Sat 5th January, 2013 @ 16:37 by :) PurpleJaguar (: - Team GR
  • 0 votes

Oh yeah - I wish I had been on GetRevising when I was learning that stuff. I only joined after my GCSEs. I found the radioactivity stuff really interesting. If you have any more questions just ask!

Answered Sat 5th January, 2013 @ 16:48 by Former Member
  • 0 votes

I know, this website is sooo helpful

and Thankyou, I will :)

Answered Sat 5th January, 2013 @ 17:03 by :) PurpleJaguar (: - Team GR
  • 0 votes

The gold leaf experiment was new and more advanced on the idea that Atoms are mainly made up of empty space. So Rutherford's had to replace Thomson's

Answered Tue 4th October, 2016 @ 21:17 by parmarn
  • 0 votes

Science isnt real and its boring so if you study it , QUIT

Answered Wed 17th January, 2018 @ 18:24 by Goodie123