Question

How many sigma and pi bonds are present in
(a)$C_2{H}_2$
(b)$C_2{H}_4$

Answer 1

In $C_2{H}_2$
$H-C\equiv C-H$
sigma bonds=3
Pi bonds=2
In $C_2{H}_4$
$H_2-C=C-H_2$
sigma bonds=5
Pi bonds=1

Hence the answer for a) is 3,2 and b)5,1