Question

oxygen is acting as an oxidizing agent in all of the following reactions except
a.
2 c(s) + o₂(g) → 2 co(g)
b.
s(s) + o₂(g) → so₂(g)
c.
2 f₂(g) + o₂(g) → 2 of₂(g)
d.
2 na(s) + o₂(g) → na₂o₂(s)
e.
2 mg(s) + o₂(g) → 2 mgo(s)

Explanation:

To determine when oxygen is not an oxidizing agent, we analyze the oxidation state of oxygen in each reaction:

• Option A: In \(O_2\), O has an oxidation state of 0. In \(CO\), O has an oxidation state of -2. Oxygen is reduced (gains electrons), so it acts as an oxidizing agent.
• Option B: In \(O_2\), O is 0. In \(SO_2\), O is -2. Oxygen is reduced, so it is an oxidizing agent.
• Option C: In \(O_2\), O is 0. In \(OF_2\), O has an oxidation state of +2 (since F is -1, and \(x + 2(-1)=0\) gives \(x = +2\)). Oxygen is oxidized (loses electrons), so it acts as a reducing agent, not an oxidizing agent.
• Option D: In \(O_2\), O is 0. In \(Na_2O_2\), O has an oxidation state of -1. Oxygen is reduced, so it is an oxidizing agent.
• Option E: In \(O_2\), O is 0. In \(MgO\), O is -2. Oxygen is reduced, so it is an oxidizing agent.

Answer:

C. \(2 F_2(g) + O_2(g)
ightarrow 2 OF_2(g)\)