Q. In a radioactive reaction $\ ^{\ }\ \ {\ _{92}X}^{232}\ \rightarrow \ \ _{82}X^{204}$ the number of $\alpha$-particles emitted is
A) 7
B) 6
C) 5
D) 4
Explanation
(a) When an$\alpha$-particle is emitted from a nucleus, the resultant nucleus reduces in mass number by 4 unit and in atomic number by 2 unit.
Loss in number$\ \ = 232 - 204 = 28$
Therefore, number of $\alpha$-particles emitted
= $\frac{28}{4}$
= 7
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.