In nitrous oxide (N₂O), nitrogen (N) bonds with oxygen (O) and with another nitrogen to form two resonance structures, as shown below.

N ≡ N⁺–O^– ↔ N^–=N⁺=O

To understand which one is more stable, let us calculate the formal charge of each structure.

i. N ≡ N⁺–O^–

Here, the two N atoms share a triple covalent bond, and one of them shares a single covalent bond with O. Let us calculate the formal charges of each atom and the net formal charge.

Nitrogen 1

V = 5, N = 2, B = 6

Therefore,

q_f = 5 – 2 – 6/2 = 0

Nitrogen 2

V = 5, N = 0, B = 8

Therefore,

q_f = 5 – 0 – 8/2 = 1

Oxygen

V = 6, N = 6, B = 2

Therefore,

q_f = 6 – 6 – 2/2 = -1

The net formal charge is: 0 + 1 – 1 = 0

ii. N^–=N⁺=O

Here, two nitrogen atoms share a double covalent bond, and one shares a double covalent bond with oxygen. Let us calculate the formal charges of each atom and the net formal charge.

Nitrogen 1

V = 5, N = 4, B = 4

Therefore,

q_f = 5 – 4 – 4/2 = -1

Nitrogen 2

V = 5, N = 0, B = 8

Therefore,

q_f = 5 – 0 – 8/2 = 1

Oxygen

V = 6, N = 4, B = 4

Therefore,

q_f = 6 – 4 – 4/2 = 0

The net formal charge is: -1 + 1 + 0 = 0

Therefore, the formal charge of nitrous oxide is zero for both the resonance structure. It means that both these structures are stable.