Identify a molecule which does not exist. - Vidyadip

MCQ

Identify a molecule which does not exist.

A
$O _{2}$
✓
$He _{2}$
C
$Li _{2}$
D
$C _{2}$

✓

Answer

Correct option: B.

$He _{2}$

b
$He _{2}=$ Total electron $=4$

$=\sigma_{1 \sigma}^{2} \sigma_{1 \sigma}^{* 2} \Rightarrow B . O .=\frac{1}{2}[ Nb - Na ]=\frac{1}{2}[2-2]=0$

Bond order $=0,$ so $He _{2}$ does not exist.

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