Fill in the blanks in the following statements.
(a) Rutherford’s -particle scattering experiment lead 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.
(d) The electronic configuration of silicon is…….. and that of sulphur is…………..
Answer:
(a) nucleus
Rutherford’s a-particle scattering experiment lead to the discovery of the nucleus.
(b) atomic number, mass number
Isotopes have same atomic number but different mass number
Example:
(c) 0 and 1
Neon: Configuration: 2, 8
Valency: 0
Chlorine: Configuration: 2,8,7
It needs 1 electron to form stable noble gas configuration.
Valency: 1
(d) silicon – Atomic number 14 – configuration - 2, 8, 4
sulphur – Atomic number 16 - configuration -2, 8, 6