Strontium-90 (atomic number 38) is a emitter

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

Problem

Strontium-90 (atomic number 38) is a

\beta^{-}

emitter. Which of the following nuclear equations correctly represents its decay, including the emitted lepton? (a)

^{90}_{38}\mathrm{Sr} \to {}^{90}_{37}\mathrm{Rb} + e^{-} + \bar{\nu}_{e}

(b)

^{90}_{38}\mathrm{Sr} \to {}^{90}_{39}\mathrm{Y} + e^{-} + \bar{\nu}_{e}

(c)

^{90}_{38}\mathrm{Sr} \to {}^{90}_{39}\mathrm{Y} + e^{-}

(d)

^{90}_{38}\mathrm{Sr} \to {}^{90}_{39}\mathrm{Y} + e^{-} + \nu_{e}