Question

question 6 (1 point)
in the reaction: $\ce{al}(s) + \ce{o_2}(g) \
ightarrow \ce{al_2o_3}(s)$, how many electrons does an atom of oxygen lose or gain?

• oxygen loses 2 electrons
• oxygen gains 2 electrons
• oxygen loses 3 electrons
• oxygen gains 3 electrons
• there is no loss or gain of electrons

Explanation:

In the reaction \( \text{Al}(s) + \text{O}_2(g)
ightarrow \text{Al}_2\text{O}_3(s) \), oxygen is in its elemental form (\( \text{O}_2 \), oxidation state 0) and in \( \text{Al}_2\text{O}_3 \), oxygen has an oxidation state of -2. To change from 0 to -2, each oxygen atom gains 2 electrons (since gaining electrons reduces the oxidation state).

Answer:

B. oxygen gains 2 electrons