Question

The number of neutrons and protons present in the nuclei of two atomic species A and B are given below.

Atomic Species	A	B
Protons	8	8
Neutrons	8	10

(i) Write the mass numbers of A and B. 

(ii) What is the relation between two species? 

(iii) Write the electronic coniguration of atoms A and B.

Answer 1

For atomic species A:

Protons = 8 

Neutrons = 8 

For atomic species B: 

Protons = 8 

Neutrons = 10 

(i) Mass number of A = 8 + 8 = 16 

Mass number of B = 8 + 10 = 18 

(ii) Both the species are isotopes of an element because they have the same atomic number or the number of protons. 

(iii) Electronic configuration of A = 2, 6 

Electronic configuration of B = 2, 6