Two successive –decays are being studied

PHYSICS · Subjective · A Level · Physics · Nuclear physics · Nuclear physics

Problem

Two successive

\alpha

–decays are being studied. (i)

^{212}\text{Po}\rightarrow{}^{208}\text{Pb}+^{4}\text{He}+Q_{1}

(ii)

^{216}\text{Rn}\rightarrow{}^{212}\text{Po}+^{4}\text{He}+Q_{2}

Given atomic masses:

^{216}\text{Rn}=216.008324\,\text{u}

^{212}\text{Po}=211.988861\,\text{u}

^{208}\text{Pb}=207.976652\,\text{u}

^{4}\text{He}=4.002603\,\text{u}

. (a) Calculate

Q_{1}

in MeV. (b) Calculate

Q_{2}

in MeV. (c) Arrange the two decays in the order of decreasing energy release and comment on the relative nuclear stability they indicate.