Which of the following nuclear decays is allowed according to conservation of nucleon…

PHYSICS · Single correct · A Level · Physics · Particles and radiation · Particles and radiation

Problem

Which of the following nuclear decays is allowed according to conservation of nucleon number, charge, and lepton number? (a)

^{14}_{6}\text{C} \to\, ^{14}_{7}\text{N} + e^{-}

(b)

^{60}_{27}\text{Co} \to\, ^{56}_{26}\text{Fe} + \alpha + \gamma

(c)

^{90}_{38}\text{Sr}^{*} \to\, ^{90}_{38}\text{Sr} + \gamma

(d)

^{131}_{53}\text{I} \to\, ^{131}_{54}\text{Xe} + e^{-} + \nu_e