Chapter 7, Problem 29P

Compare the bonding in formic acid $\left(\text{HCOOH}\right)$ with that in its conjugate base formate ion $\left({\text{HCOO}}^{-}\right).$ Each molecule has a central carbon atom bonded to the two oxygen atoms and to a hydrogen atom. Draw Lewis diagrams, determine the steric numbers and hybridization of the central carbon atom, and give the molecular geometries. How do the $\pi$ orbitals differ in formic acid and the formate molecular ion? The bond lengths of the $\text{C}-\text{O}$ bonds in $\text{HCOOH}$ are 1.23 (for the bond to the lone oxygen) and $1.36\text{Å}$ (for the bond to the oxygen with a hydrogen atom attached). In what range of lengths do you predict the $\text{C}-\text{O}$ bond length in the formate ion to lie?