Question

Nucleus P is converted into S through the following reactions
$P\to Q+\alpha$
$Q\to R+e^{–}$
$R\to S+e^{–}$
Now a student figures out 4 conclusions from the above reactions as given below.
(i)R and S are isotopes
(ii) P and S are isotopes
(iii) Q and S are isotopes
(iv) Q and R are isotopes

• A. Only (ii) is correct
• B. (ii) and (iii) are correct
• C. (iii) and (iv) are correct
• D. (ii), (iii) and (iv) are correct

Answer 1

The correct option is A Only (ii) is correct

${}_z{P}^A{\to }_{(z-2)}{Q}^{A-4}{+}_{2}H{e}^4$
${}_{(z-2)}{Q}^{(A-4)}{\to }_{(z-1)}{S}^{(A-4)}+e^{-}$
${}_{z-1}{P}^{(A-4)}{\to }_z{S}^{(A-4)}+e^{-}$
P and S are isotopes