Question

In the reaction given below ${ }_{86} A^{222} \longrightarrow { }_{84} B^{210}$ and $ \beta$ -particles are emitted ?

• A. $ 6\alpha ,3 \beta $
• B. $ 3\alpha ,4\beta $
• C. $ 4\alpha ,3\beta $
• D. $ 3\alpha ,6\beta $

Answer 1

Answer: (B)

${ }_{86} A^{222} \longrightarrow { }_{84} B^{210}$
Decrease in mass number $=222-210$
$=12$
$\therefore $ Number of $\alpha$-particles emitted
$=\frac{12}{4}=3$
${ }_{86} A^{222} \longrightarrow { }_{80} X^{210} \longrightarrow { }_{84} B ^{210}$
Increase in atomic number $=84-80=4$
$\therefore $ Number of $\beta$-particles emitted $=4$