Question

oxygen is acting as an oxidizing agent in all of the following reactions excepta.\\( 2\\ c(s) + o_2(g) \
ightarrow 2\\ co(g)\\)b.\\( s(s) + o_2(g) \
ightarrow so_2(g)\\)c.\\( 2\\ f_2(g) + o_2(g) \
ightarrow 2\\ of_2(g)\\)d.\\( 2\\ na(s) + o_2(g) \
ightarrow na_2o_2(s)\\)e.\\( 2\\ mg(s) + o_2(g) \
ightarrow 2\\ mgo(s)\\)

Explanation:

To determine when oxygen is not an oxidizing agent, we check the oxidation state of O in each reaction. An oxidizing agent is reduced (oxidation state decreases).

• In A, B, D, E: O in \(O_2\) (oxidation state 0) becomes -2 (in CO, \(SO_2\), \(Na_2O_2\) (O is -1, still reduced from 0), MgO), so O is reduced (oxidizing agent).
• In C: O in \(O_2\) (0) becomes +2 in \(OF_2\) (since F is -1, 2*(-1) + x = 0 → x=+2). Oxidation state of O increases (oxidized), so \(O_2\) is a reducing agent here, not an oxidizing agent.

Answer:

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