In CO2, hybridization of carbon is:
sp
In CO2 molecule C is sp hybridized.
Two sp-hybridised orbitals of C-atom overlap with two p-orbitals of O-atoms to make two sigma (σ) bonds, while the other two electrons on C-atoms are involved in pπ−pπ bonding with O-atoms. As a result CO2 is linear, monomeric covalent compound.