Put a tick(✓) against the correct choice and cross(x) against the wrong choice in questions 15, 16 and 17. Rutherford’s alpha–particle scattering experiment was responsible for the discovery of (a) Atomic nucleus (b) Electron (c) Proton (d) Neutron
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution:
(a) Atomic nucleus
Isotopes of an element have
(a) The same physical properties
(b) Different chemical properties
(c) Different number of neutrons
(d) Different atomic numbers
Solution:
(c) Different number of neutrons
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