Question

Stable nuclei having number of neutrons less than number of protons are:

• A. ${}_1^{1}H$
• B. ${}_2^{3}He$
• C. ${}_5^{11}B$
• D. ${}_6^{11}C$

Answer 1

Answer: (A), (B)

The correct options are
A ${}_2^{3}He$
B ${}_1^{1}H$

Stable nuclei having number of neutrons less than number of protons are
${}_1^{1}H$ and ${}_2^{3}He$
${}_1^{1}H$ has only one nucleon. Hence, stable.
${}_2^{3}He$ has magic number of protons (2).

Hence, the correct options are $\text{A}$ and $\text{B}$