Q. The radioactive decay of uranium into thorium is expressed by the equation $\ _{92}^{238}U \rightarrow \ _{90}^{234}Th + X$, where $'X'$ is
A) An electron
B) A proton
C) A deuteron
D) An alpha particle
Explanation
(d) $\ _{92}U^{238} \rightarrow_{\ 90}Th^{234} +_{2}He^{4}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.