In the molecule $HCN$, how many sigma and pi bonds are present?

In $C_2{H}_4$ (ethene), which type of bond is formed by the sideways overlap of p orbitals?

Which types of orbital overlap occur between two adjacent atoms to form a $doublebond$?

Which type of atomic orbitals overlap to form $\pi$ bonds in organic molecules?

Which statement is correct regarding a $\pi$ bond?

Which types of orbital overlap are present in the bonding of a cumulene molecule?

Consider the molecule $C_2{H}_4$ (ethene), where one of the carbon atoms is highlighted. In how many sigma bonds does the highlighted carbon atom participate?

In a molecule of cumulene with the formula $C_4{H}_4$, how many sigma ($\sigma$) and pi ($\pi$) bonds are present?

Which type of bond allows free rotation around the bond axis?