In the decay series `._(92)U^(238)` to `._(82)Pb^(206)`, how many `alpha`-paritcles and how many `beta^(ɵ)`-particles are emitted?

Options

A. 6,8
B. 9,6
C. 8,8
D. 8,6

Answer

D

Explanation

`._(92)U^(238) rarr ._(82)Pb^(206) + x ._(2)He^(4) + y ._(-1)e^(0)`
Equating mass number on both sides
`238 = 206 + x xx 4 + y xx 0`
`:. X = (238 - 206)/(4) = 8`
Equating atomic number on both sides
`92 = 82 + 2 xx 8 + y (-1)`
`:. y = 98 - 92 = 6`