Question

$\beta$-decay means emission of electron from

• A. innermost electron orbit
• B. a stable nucleus
• C. outermost electron orbit
• D. radioactive nucleus

Answer 1

Answer: (D)

$\beta$ - emission takes place from a radioactive nucleus a
${}_{15}^{32}P\stackrel{\beta }{\to }{}_{16}^{32}S+{}_{-1}{e}^0+\bar{v}$
${}_{15}^{32}P\stackrel{\beta }{\to }{}_{16}^{32}S+{}_{-1}{e}^0+\bar{v}$
where $\bar{v}$ is the anti-neutrino.
In ${\beta }^{+}$ decay a positron is emitted as
${}_{11}^{22}Na{\to }_{11}^{22}Ne{+}_{+1}{e}^0+v$
where $v$ is the neutrino.