JEE Main 2026 · 22 January · morning · Single correct · +4 / −1
The formal charges on the atoms marked as (1) to (4) in the Lewis representation of HNO₃ molecule respectively are
- (a) 0,0,-1,+1
- (b) 0,-1,0,+1
- (c) 0,+1,0,-1
- (d) +1,0,0,-1
Answer and solution
Answer (c) 0,+1,0,-1
Solution
Chemistry ma’am · 3 steps
For each atom, take valence electrons, subtract lone-pair electrons and half the bonding electrons.
FC = V - L - B/2
- Read the structure. V is the valence electron count of the free atom (5 for N, 6 for O). L is the number of lone-pair electrons on the atom and B is the number of electrons in the bonds it forms. Count each from the figure.
Atom Bonds and lone pairs V - L - B/2 Formal charge (1) O bonded to H 2 single bonds, 2 lone pairs 6 - 4 - 2 0 (2) N 2 single bonds and 1 double bond, no lone pair 5 - 0 - 4 +1 (3) O with the double bond 1 double bond, 2 lone pairs 6 - 4 - 2 0 (4) O with a single bond 1 single bond, 3 lone pairs 6 - 6 - 1 -1 - Check the total. 0 + (+1) + 0 + (-1) = 0, and H is also 0. That matches a neutral HNO₃ molecule.
- So. The formal charges on atoms (1) to (4) are 0, +1, 0, -1, which is option (c).
The idea to keep. Formal charge depends only on the atom's own lone pairs and bonds. A neutral molecule must add up to zero. N with four bonds is +1, and O with one bond and three lone pairs is -1.
Answer from the NTA final answer key. Solution by PrepWiser.