Question

Calculate the total number of α- and β-particles emitted in the nuclear reaction ${}_{92}{U}^{238}{⟶}_{82}P{b}^{214}.$

(IIT-JEE, 2009)

• A. 4
• B. 6
• C. 8
• D. 9

Answer 1

The correct option is C 8

${}_{92}{U}^{238}\to {}_{82}P{b}^{214}+x{}_{2}H{e}^4+y{}_{-1}{e}^0$

Equating atomic number on both sides

238 = 214 + x x 4 + y x 0

∴ x = 6

Hence, 6 α-particles are emitted.

Equating atomic number on both sides

92 = 82 + 6 x 2 + y (-1)

∴ y = 2

Hence, 2 β-particles are emitted.

Therefore, total 8 particles (6α, 2β) are emitted.