Exam-style question
Try this first
Explain why the plum‑pudding model was replaced by the Rutherford model of the atom.
Model answer
What a good answer should say
- The plum‑pudding model could not account for the large scattering angles observed when alpha particles were directed at thin gold foils; the Rutherford model, with a small dense nucleus, explains these angles by Coulomb repulsion between the positively charged nucleus and the alpha particles.
Explanation
Why this works
The question tests the student’s ability to evaluate competing atomic models using experimental evidence. The answer must link the observed alpha‑particle scattering to the need for a compact nucleus, demonstrating understanding of how experimental data can invalidate a theoretical model.
Common mistake
No common mistake is linked to this question yet.