MCQ
Which species does not exist
- A${(SiC{l_6})^{2 - }}$
- ✓${(CC{l_6})^{2 - }}$
- C${(GeC{l_6})^{2 - }}$
- D${(SnC{l_6})^{2 - }}$
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[Assume steam to be an ideal gas. Given $A _{ vap } H ^{\ominus}$ for water at $373 \,K$ and $1\, bar$ is $41.1 \,kJ\, mol ^{-1} ; R =$ 8.31 $J\,K ^{-1} \,mol ^{-1}$ ]
the number of sigma and pi bonds respectively are