# How many electrons are involved in sigma-"bonding" in the "acetylene" molecule?

Well, formally, there are 6 electrons involved in the $\sigma - \text{bonding interaction}$. No?
We gots $\text{acetylene}$, $H - C \equiv C - H$. There are $2 \times C - H$ bonds, and $1 \times C - C$ bond, and each bond formally requires 2 electrons, and thus there are 6 electrons involved.
Of course there are $2 \times C - C$ $\pi$ bonds above and below the plane of the $\sigma - \text{bonds}$ in 3 dimensions.