Question

The number of $\sigma -$ and $\pi -bonds$ present in $pent-4-ene-1-yne$ is:

• A. $10,3$
• B. $4,9$
• C. $3,10$
• D. $9,4$

Answer 1

Answer: (A)

$10,3$

$\stackrel{1}{CH}\equiv \stackrel{2}{C}-\stackrel{3}{C{H}_2}-\stackrel{4}{CH}=\stackrel{5}{C{H}_2}$
No. of $\sigma -bonds-4(C-C)+6(C-H)=10$
No. of $\pi -bonds-1(C=C)+2(C\equiv C)=3$