Final answer:
The oxidation state of nitrogen (N) did not change during the reaction because the oxidation number of nitrogen remained +2 in both reactants (NO) and products (NOCl).
Step-by-step explanation:
In order to determine if the oxidation state of nitrogen (N) changed during a reaction, we must assign oxidation numbers to the atoms in the reactants and products. In the equation 2NO + Cl2 → 2NOCl, we start by knowing that the oxidation number of Cl in Cl2 is 0 because it is an element in its standard state. For NO, we assume that oxygen has an oxidation number of -2. As there are two oxygen atoms, that is a total of -4 charge. To balance this in NO, nitrogen must have an oxidation number of +2. In the product NOCl, chlorine typically has an oxidation number of -1, which would still yield an oxidation number of +2 for nitrogen. Since there is no change in the oxidation number of nitrogen from reactants (+2) to products (+2), it means nitrogen was neither oxidized nor reduced in this reaction. Therefore, we can conclude that the oxidation state of nitrogen did not change during Reaction 2.