When absorbs a neutron it forms the compound nucleus * which can split through…

PHYSICS · Multi-part · A Level · Physics · Nuclear physics · Nuclear physics

Problem

When

^{235}\text{U}

absorbs a neutron it forms the compound nucleus

^{236}\text{U}

* which can split through different channels. Consider the two possibilities given below (two neutrons are emitted in each case): Channel A:

^{236}\text{U}\;\to\;^{144}\text{Ba}+^{92}\text{Kr}+2\,^{1}\text{n}

Channel B:

^{236}\text{U}\;\to\;^{134}\text{Te}+^{100}\text{Zr}+2\,^{1}\text{n}

(i) Using the atomic masses

^{236}\text{U}=236.0456\,\text{u}

^{144}\text{Ba}=143.9229\,\text{u}

^{92}\text{Kr}=91.9262\,\text{u}

^{134}\text{Te}=133.9114\,\text{u}

^{100}\text{Zr}=99.9161\,\text{u}

and

^{1}\text{n}=1.00866\,\text{u}

, calculate the energy released

Q_{\!A}

for Channel A. Take

1\,\text{u}=931.5\,\text{MeV}/c^{2}

. (ii) Repeat the calculation for Channel B to obtain

Q_{\!B}

. (iii) Which channel is energetically more favourable? By how much energy (in \text{MeV}) do the two channels differ?