Question

An unknown stable nuclide after absorbing a neutron emits an electron, and the new nuclide splits spontaneously into two alpha particles. The unknown nuclide can be

• A. ${}_{4}B{e}^9$
• B. ${}_{3}L{i}^7$
• C. ${}_{2}H{e}^2$
• D. ${}_5{B}^{10}$

Answer 1

The correct option is B ${}_{3}L{i}^7$

A neutron is a result of beta decay and as nucleus perform beta decay, it increases one proton. And the consequent two alpha decay also suggest that there are atleast 4 protons required. ${}_3{Li}^7$ best suit the condition because 1 beta decay increases the proton to 4.

Ans: ${}_3{Li}^7$