Q. An artificial radioactive decay series begins with unstable $\ _{94}^{241}Pu$. The stable nuclide obtained after eight $\alpha -$decays and five $\beta -$decays is
A) $\ _{83}^{209}Bi$
B) $\ _{82}^{209}Pb$
C) $\ _{82}^{205}Ti$
D) $\ _{82}^{201}Hg$
Explanation
(a) Mass number decreases by $8 \times 4 = 32$
Atomic number decreases by $8 \times 2 - 5 = 11$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.