Question

In the reaction \( 3Mg + N_2 \rightarrow Mg_3N_2 \), the oxidation number of Mg changes is:

• A. 0 → +3
• B. 0 → +6
• C. 0 → +2
• D.

Hint:

In reactions involving ionic compounds, the oxidation number of metals like magnesium can be determined based on the charges of the other elements. Magnesium typically forms a +2 or +3 oxidation state when reacting with nonmetals like nitrogen.

Answer 1

The Correct Option is A

In this reaction, magnesium (Mg) reacts with nitrogen (N\(_2\)) to form magnesium nitride (Mg\(_3\)N\(_2\)). - The oxidation state of magnesium (Mg) in its elemental form (Mg) is 0. - In the product \( Mg_3N_2 \), magnesium is part of the ionic compound. Since nitrogen typically has an oxidation state of -3 in ionic compounds, the total oxidation state for the two nitrogen atoms is -6. To balance the charge of the compound (which must be neutral), the oxidation state of each magnesium atom must be +3. Thus, magnesium changes its oxidation number from 0 to +3 during the reaction.