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 $=4$
$He _{2}=$ 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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