Question

The number of neutron in Deuterium is :

• A. 1
• B. \N
• C. 2
• D. 3

Answer 1

The correct option is A 1

Deuterium is ${}_1^{2}H$
$\text{Number of neutron= atomic mass- atomic number}$
$\text{Number of neutron= 2 - 1}=1$
Hence, correct option is a.