# What is the hybridization of each carbon in this molecule?

It is $s {p}^{3} \mathmr{and} s {p}^{2}$
While the second carbon is $s {p}^{2}$ because it forms a double bond with oxygen. In $s {p}^{2}$ hybridisation the 2s orbital hybridises with only two 2p orbitals leaving the other 2p orbital unhybridised. The orbitals in $s {p}^{2}$ with be completed with one more electron each by sharing covalently with the C, O and the other O.
The unhybridised p orbital will be completed with the other sharing electron of the oxygen. This with form the $\pi$ bond in the carbon-oxygen double bond.