Practice question · Multiple choice
Why could Thomson's plum-pudding model not survive the gold-foil result?
Hints
- The model did contain positive charge, the question is how it was distributed.
- Spread-out charge gives weak forces everywhere and cannot reverse a fast projectile.
Show the answer
D. It spread positive charge too thinly to deflect an alpha particle backwards
Why
Plum pudding did contain both charges; its failure was the distribution. Charge smeared over the whole atom produces only gentle deflections, never the large-angle rebounds Rutherford measured.
Practise Atomic Models and Isotopes
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