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Question Question 4
What do you think would be the observation if the ∝–particle scattering experiment is carried out using a foil of a metal other than gold?
If the ∝–particle scattering experiment is carried out using a foil of a metal (as thin as gold) other than gold, then also the observation would be same because the structure of an atom, when considered individually is same.
However, other metals are not as malleable as gold so it is difficult to turn those metals into such thin sheets. If thick foil is used then it will result in the change of scattering angles which might affect the predictions of the experiment.
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Science | Chapter 4: Structure of the AtomWeb Content — Quick Reference
Chapter 4: Structure of the Atom — Quick Reference
Quick Revision Points
- Thomson: positive sphere with embedded electrons (plum pudding)
- Rutherford: nucleus (dense, positive) + electrons in orbits. Limitation: electron should spiral in
- Bohr: electrons in fixed energy levels (shells K, L, M, N)
- Max electrons per shell: 2n² (K=2, L=8, M=18, N=32); outermost max 8
- Z = protons = electrons; A = protons + neutrons; neutrons = A − Z
- Isotopes: same Z, different A. Isobars: different Z, same A
- Valency: ≤ 4 → valency = outermost e⁻; > 4 → valency = 8 − outermost e⁻
Exam Tips for Chapter 4
- Read the detailed chapter notes for complete coverage of all NCERT topics.
- Practice all NCERT in-text and back exercise questions — they are frequently asked in exams.
- Focus on comparison tables, diagrams, and definitions — these are high-scoring areas.
- For numericals (if applicable), practice at least 20 problems of varying difficulty.
- Refer to the practice question bank (200+ questions) for thorough preparation.
Related Resources
- Detailed Notes: ch04-structure-of-the-atom.html
- Practice Questions: 100+ questions with answers in 05-practice-questions/
- Chapter Test: 30-mark test paper in 06-tests/chapter-tests-30marks/
- Formula Sheet: Complete formula reference in 03-teacher-aid/formula-sheet.html