Question

The sum of sigma (\( \sigma \)) and pi (\( \pi \)) bonds in Hex-1,3-dien-5-yne is:

Hint:

In organic compounds, double bonds contribute one \( \sigma \)-bond and one \( \pi \)-bond, while triple bonds contribute one \( \sigma \)-bond and two \( \pi \)-bonds.

Answer 1

Hex-1,3-dien-5-yne has the following structure:
- 1 single bond between carbon atoms (sigma bonds).
- 2 double bonds (each having one sigma and one pi bond).
- 1 triple bond (with one sigma and two pi bonds).
- Single bonds between carbon and hydrogen atoms.
The total number of bonds is:
- \( 6 \) carbon-hydrogen single bonds.
- \( 6 \) carbon-carbon sigma bonds (from the backbone of the chain).
- 2 pi bonds from the double bonds.
- 2 pi bonds from the triple bond. Thus, the total number of \( \sigma \) and \( \pi \) bonds is: - \( \sigma \)-bonds: \( 6 \, ({C-H bonds}) + 6 \, ({C-C single bonds}) + 1 \, ({C-C triple bond}) = 13 \) - \( \pi \)-bonds: \( 2 \, ({from the double bonds}) + 2 \, ({from the triple bond}) = 4 \) So, the sum of sigma and pi bonds is \( 13 + 4 = 17 \).