Practice Reduction in Chemistry

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

The gain of electrons by an atom, ion, or molecule, decreasing its oxidation state.

Grabbing electrons. The charge gets 'reduced' (becomes more negative).

Example 1

easy
In the reaction 2\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO}, identify which species is reduced.

Example 2

medium
In a blast furnace, iron ore is reduced: \text{Fe}_2\text{O}_3 + 3\text{CO} \rightarrow 2\text{Fe} + 3\text{CO}_2. Identify the reducing agent.

Example 3

easy
In the reaction \text{Cu}^{2+} + 2e^- \rightarrow \text{Cu}, is copper being oxidized or reduced?

Example 4

medium
In the reaction \text{CuO} + \text{H}_2 \rightarrow \text{Cu} + \text{H}_2\text{O}, which substance is reduced?