Final answer:
The oxidation number of nitrogen in NaNO3 is +5, which is determined by balancing the oxidation numbers of sodium and oxygen to maintain the neutral charge of the compound.
Step-by-step explanation:
The oxidation number of nitrogen (N) in sodium nitrate (NaNO3) can be determined by considering the charges on the sodium (Na) and oxygen (O) atoms and the overall neutral charge of the compound.
The sodium atom, being a Group 1 element, always has an oxidation number of +1. Oxygen typically has an oxidation number of -2. Since there are three oxygen atoms, their total contribution is -6. Therefore, the nitrogen's oxidation number must balance the charges to zero. The calculation is as follows:
x + 3(-2) = 0, where x represents the oxidation number of nitrogen. Solving for x yields:
x + (-6) = 0
x = +6
Therefore, the oxidation number of nitrogen in NaNO3 is +5.