Question

What is the oxidation number of Nitrogen in HNO2?

+1
-1
+3
-3

Answer 1

The oxidation number of Nitrogen in HNO2 is +3. This is determined using the fact that oxygen has an oxidation number of -2, and hydrogen has an oxidation number of +1 in the compound.

Step-by-step explanation:

The oxidation number of Nitrogen in HNO2 (nitrous acid) is +3. When determining oxidation states, we use the rule that oxygen normally has an oxidation number of -2. Since there are two oxygen atoms in nitrous acid, their combined oxidation number is -4. Knowing hydrogen has an oxidation number of +1, we can set up an equation to find the oxidation state of nitrogen (N) in HNO2. Let x represent the oxidation number of nitrogen:

H (+1) + N (x) + 2 O (-2 each) = 0 (since the compound is neutral)

1 + x - 4 = 0

x - 3 = 0

x = +3

Therefore, the oxidation number of nitrogen in HNO2 is +3, which corresponds to one of the given options.

Answer 2

The correct answer is +3

That is because the number of the entire molecule must always be 0. Since O2 equals -4 because individual oxygen atoms are -2, and Hydrogen (H) is +1, then you can see that H +1, + 3 from N, -4 from O2 = 0.