The formal charge on nitrogen in nitric oxide (NO) is +1.
To understand how this charge is determined, we can look at the structure of nitric oxide. Nitric oxide consists of one nitrogen atom and one oxygen atom. In its commonly accepted Lewis structure, the nitrogen atom is bonded to the oxygen atom with a double bond, and there is one unpaired electron on nitrogen.
To calculate the formal charge, we use the formula:
Formal Charge = Valence Electrons – (Nonbonding Electrons + 0.5 * Bonding Electrons)
For nitrogen, which is in Group 15 of the periodic table, it has 5 valence electrons:
- Valence Electrons = 5
In NO, nitrogen has:
- Nonbonding Electrons = 1 (the unpaired electron)
- Bonding Electrons = 4 (from the double bond to oxygen, counted as two pairs)
Plugging these into the formula gives:
Formal Charge = 5 – (1 + 0.5 * 4) = 5 – (1 + 2) = 5 – 3 = +1
Thus, the formal charge on the nitrogen atom in nitric oxide is +1. This positive charge indicates that nitrogen is less electron-rich compared to its neutral state in this molecule.