Question

The molecular electronic configuration of $B{e}_2$ is:

• A. $\sigma 1s^2{\sigma }^{\ast }1s^2\sigma 2s^2{\sigma }^{\ast }2p^2$
• B. $KK\sigma 2s^2$
• C. $\sigma 1s^2{\sigma }^{\ast }1s^2\sigma 2s^2{\sigma }^{\ast }2s^2$
• D. none of the above

Answer 1

Answer: (C)

Total no. of electrons in $B{e}_2=8$.
Electronic configuration according to molecular orbital theory:
$\sigma 1s^2,{\sigma }^{\ast }1s^2,\sigma 2s^2={\sigma }^{\ast }2s^2$