Get Answers to all your Questions

header-bg qa

Q.13.14  The nucleus _{10}^{23}\textrm{Ne} decays by \beta ^{-} emission. Write down the \beta-decay equation and determine the maximum kinetic energy of the electrons emitted. Given that:

                  (i) m (_{10}^{23}\textrm{Ne} ) = 22.994466 \; u

                 (ii) m (_{11}^{23}\textrm{Na} ) = 22.089770 \; u
                

Answers (1)

best_answer

The \beta decay equation is

_{10}^{23}\textrm{Ne}\rightarrow _{11}^{23}\textrm{Na}+e^{-}+\bar{\nu }+Q

\\\Delta m=m(_{10}^{23}\textrm{Ne})-_{11}^{23}\textrm{Na}-m_{e}\\ \Delta m=22.994466-22.989770\\ \Delta m=0.004696u

 (we did not subtract the mass of the electron as it is cancelled because of the presence of one more electron in the sodium atom)

Q=0.004696\times931.5

Q=4.3743 eV

The emitted nucleus is way heavier than the \beta particle and the energy of the antineutrino is also negligible and therefore the maximum energy of the emitted electron is equal to the Q value.

Posted by

Sayak

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads