Question

A: Tetracyanomethane
B: Carbondioxide
C: Benzene
C: $1,3-buta-di-ene$
Ratio of $\sigma$ and $\pi$:

• A. in A and B are equal
• B. in C and D are equal
• C. is same in A, B, C, and D
• D. in B and D are equal

Answer 1

The correct option is A in A and B are equal

$a:$ Tetracyanomethane, see the figure i. where $\sigma$ bond $=8$, ratio$=1$, $\pi$ bond $=8.$

$b:$ Carbondioxide, $O=C=O\sigma =2\pi =2$, ratio$=1.$

$c:$ Benzene, see the figure ii, where $\sigma$ bond$=12,$ $\pi$ bond $=3$, ratio $=4.$

$d:$ $1,3-$buta-di-ene, see the figure iii, where $\sigma$ bond $=9,$ $\pi$ bond $=2,$ ratio $=\frac{9}{2}.$

$\therefore A=B$