Question

$M_{n}$ and $M_{p}$ represent mass of neutron and proton respectively. If an element having atomic mass $M$ has $N$ neutrons and $Z$ protons, then the correct relation will be:

• A. $M<\left[N M_{n}+Z M_{p}\right]$
• B. $M>\left[ NM _{ n }+ ZM _{ p }\right]$
• C. $M=\left[N M_{n}+Z M_{p}\right]$
• D. $M=[N]\left[M_{n}+M_{p}\right]$

Answer 1

Answer: (A)

Actual mass of the nucleus is always less than total mass of nucleons, so $M <\left( NM _{ n }+ ZM _{ p }\right)$