Classic chemistry experiments
39.
99
The reaction between a
metal oxide and a dilute
acid
Topic
Acids and bases.
Timing
30 min.
Description
Copper(II) oxide is dissolved in hot dilute sulfuric acid to give copper(II) sulfate.
Apparatus and equipment (per group)
▼ Tripod
▼ Gauze
▼ Filter paper
▼ Bunsen burner
3
▼ 100 cm Conical flask
3
▼ 100 cm Beaker
▼ Filter funnel
▼ Spatula.
Chemicals (per group)
–3
▼ Sulfuric acid 0.4 mol dm
▼ Three spatula measures copper(II) oxide (Harmful)
Teaching tips
Whatman qualitative No. 1 filter papers work well for this experiment. The teacher
may need to remind students how to fold filter paper. A fluted filter paper allows faster
filtration.
Background theory
Acid + base → salt + water.
Safety
Wear eye protection. Keep test-tubes facing away while heating.
Answers
1. Unreacted copper(II) oxide.
2. Copper(II) sulfate.
3. CuO(s) + H2SO4(aq) → CuSO4(aq) + H2O(l)
4. The water can be evaporated, the solid copper(II) sulfate crystallises.
100
Classic chemistry experiments
The reaction between a
metal oxide and a dilute
acid
Introduction
Many metal oxides react with dilute acid. In this experiment copper(II) oxide is reacted
with dilute sulfuric acid.
Filter funnel
Filter paper
Residue
Beaker
Conical flask
Copper oxide
and sulfuric
acid mixture
Filtrate
What to do
3
1. Pour about 20 cm of dilute sulfuric acid into a beaker.
2. Heat on a tripod and gauze using a Bunsen burner until the acid just boils.
3. Add copper(II) oxide to the hot acid, a spatula measure at a time and stir after each
addition, continue until no more dissolves.
4. Filter the mixture, while still hot, into a conical flask.
Safety
Wear eye protection.
Questions
1. What is the residue on the filter paper?
2. What does the filtrate contain?
3. Write an equation for the reaction between solid copper(II) oxide and dilute
sulfuric acid.
4. How could the solid product be isolated from the filtrate?