Question

A nuclear transformation is denoted by $X(n,\alpha {)}_3^{7}Li$. Which of the following is the nucleus of element $X$?

• A. ${}_6^{12}C$
• B. ${}_5^{10}B$
• C. ${}_5^{9}B$
• D. ${}_4^{11}Be$

Answer 1

The correct option is B ${}_5^{10}B$

${}_y^x\text{X}$ + ${}_0^1\text{n}$ $\to$ ${}_2^4\text{He}$ + ${}_3^7\text{Li}$

On balancing atomic number and mass number on both sides, we get

x=10 and y=5

so correct option is ${}_5^{10}\text{B}$