Decreasing Order of Oxidation States in Nitrogen Compounds

Use fixed rules and solve for N. Oxygen is -2 and hydrogen is +1. In HNO3: (+1) + N + 3(-2) = 0, so N = +5. In NO: N + (-2) = 0, so N = +2. In NH4Cl the NH4+ ion has 4 H (each +1) and total +1, so N + 4 = +1, N = -3. Once you have each number, arrange them from high to low.

An element bonded only to identical atoms of itself has oxidation state 0. In N2 both nitrogen atoms are the same, so neither pulls electrons more than the other. The rule is: any pure element (N2, O2, Na, S8) has oxidation number 0.

+5 is higher. Oxidation state is like a number line: +5 > +2 > 0 > -2 > -3. Students often wrongly treat -3 as large because it has a big digit. In redox, sign decides rank, so -3 is the lowest (most reduced) state of nitrogen.

Nitrogen ranges from -3 (NH3, NH4+) to +5 (HNO3, N2O5). Common in-between values: -2 (N2H4), -1 (NH2OH), 0 (N2), +1 (N2O), +2 (NO), +3 (HNO2, N2O3), +4 (NO2). This wide range is why nitrogen appears so often in redox and disproportionation questions.

No, you always report the oxidation state per atom. In N2O5 there are 2 N atoms sharing +10 total, so each N is +5, not +10. Divide the total charge among the atoms of that element to get the per-atom oxidation number used for ranking.

+5, seen in HNO3, N2O5 and nitrate (NO3-). It matches nitrogen's group number in the periodic table (group 15).

-3, seen in ammonia (NH3) and ammonium salts like NH4Cl. This is the most reduced form of nitrogen.

Nitrogen has 5 valence electrons and can either gain 3 (giving -3) or lose up to 5 (giving +5). Every whole number between -3 and +5 exists in a real nitrogen compound, which is why NEET tests this range often.

Valency is the number of bonds (nitrogen is usually 3 or 4), while oxidation state includes sign and depends on which atom is more electronegative. In HNO3 nitrogen's valency is 4 but its oxidation state is +5.