Fill in the blanks in the following statements (a) Rutherford’s α-particle scattering experiment led to the discovery of the ——— (b) Isotopes have same ———but different———. (c) Neon and chlorine have atomic numbers 10 and 17 respectively. Their valencies will be———and—— —respectively. The electronic configuration of silicon is ———and that of sulphur is ———
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
- Rutherford’s α-particle scattering experiment led to the discovery of the atomic nucleus
- Isotopes have same atomic number but different mass number
- Neon and chlorine have atomic numbers 10 and 17 Their valencies will be 0 and 1
respectively.
- The electronic configuration of silicon is 8.4 and that of sulphur is 2.8.6
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