(a)[2]
Explain what the term isotope means.
(b(i))[1]
In a nuclear reaction, proton number and neutron number are conserved. Apart from proton number and neutron number, state one quantity that is conserved in a nuclear reaction.
(b(ii))[3]
When a uranium-235 nucleus absorbs a neutron, this reaction may occur: $^{235}_{92}\text{U} + ^{a}_{b}\text{n} \rightarrow ^{141}_{x}\text{Ba} + ^{y}_{36}\text{Kr} + 3\,^{a}_{b}\text{n}$. State the values of $a$, $b$, $x$ and $y$.
(c)[2]
When the nucleus of $^{238}_{92}\text{U}$ absorbs a neutron, the nucleus decays, emitting an $\alpha$-particle. State the proton number and nucleon number of the nucleus produced by the emission of the $\alpha$-particle.