Q.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.               [2023]

Assertion A: The nuclear density of nuclides B510,36Li,2656O,1020Ne and Bi83209 can be arranged as

ρBiN>ρFeN>ρNeN>ρBN>ρLiN.

Reason R: The radius R of nucleus is related to its mass number A as R=R0A1/3, where R0 is a constant.

In the light of the above statement, choose the correct answer from the options given below:

1 Both A and R are true and R is the correct explanation of A  
2 A is false but R is true  
3 A is true but R is false  
4 Both A and R are true but R is NOT the correct explanation of A  

Ans.

(2)

R=R0A1/3, using this

ρ=M43πR3=Amp43πR03A=mp43πR03

ρ is independent of mass number.

 A is false.