Valence Bonding Descriptions for Triple Bonds

[Stuti Pradhan 2J]

How do you use valence bonding descriptions when it comes to triple bonds? For example, you use valence bonding descriptions such as (C2sp^2, C2sp^2) to describe a bond between two carbon atoms with trigonal planar geometries, but in HCN, how would you describe the triple bond between the C and the N? I know if it was just a double bond in something like C2H4, you would say (C2p, C2p) to describe the C-C double bond (in addition to the sigma bond), so for the triple bond would it be (C2p^2, N2p^2) since they have 2 unhybridized p-orbitals that are being used for bonding?

Thank you in advance!

[Margia Adriano 2A]

Hi! I believe you're correct. The carbon has two hybridized orbitals that are 2sp² for the two regions of electron density. This leaves us with two unhybridized 2p orbitals for the remaining two valence electrons that make up the two pi bonds in the triple bond between carbon and nitrogen.