Bond order and formal charge of oxygen atoms in HCO2- ion

Bond order of oxygen atoms in HCO2- ion:

The bond order is the number of chemical bonds between a pair of atoms. The bond order of each oxygen atom in HCO2- ion can be calculated using the following formula:

Bond order = 1/2 (number of bonding electrons - number of anti-bonding electrons)

For the oxygen atom in the carbonyl group (C=O), the bond order is:

Bond order = 1/2 (4 - 2) = 1

This means that the oxygen atom in the carbonyl group has a single bond with the carbon atom.

For the oxygen atom in the carboxylate group (O-), the bond order is:

Bond order = 1/2 (6 - 2) = 2

This means that the oxygen atom in the carboxylate group has a double bond with the carbon atom.

Formal charge of oxygen atoms in HCO2- ion:

The formal charge is the charge assigned to an atom in a molecule or ion based on the assumption that the electrons are shared equally between the atoms. The formal charge of each oxygen atom in HCO2- ion can be calculated using the following formula:

Formal charge = valence electrons - non-bonding electrons - 1/2 bonding electrons

For the oxygen atom in the carbonyl group (C=O), the formal charge is:

Formal charge = 6 - 2 - 1/2(2) = 0

This means that the oxygen atom in the carbonyl group has a formal charge of 0, indicating that it is neutral.

For the oxygen atom in the carboxylate group (O-), the formal charge is:

Formal charge = 6 - 2 - 1/2(4) = -1

This means that the oxygen atom in the carboxylate group has a formal charge of -1, indicating that it has gained an extra electron and has a negative charge.

Summary:

- The bond order of the oxygen atom in the carbonyl group (C=O) is 1, indicating a single bond with the carbon atom. The bond order of the oxygen atom in the carboxylate group (O-) is 2, indicating a double bond with the carbon atom.
- The formal charge of the oxygen atom in the carbonyl group (C=O) is 0, indicating neutrality. The formal charge of the oxygen atom in the carboxylate group (O-) is -1, indicating a negative charge.

B.O= total no. of bonds between two atoms in all structure/total no. of R.S. & formal charge=(valance e-) - (L.P e-) - 1/2(shared or bonding e-)