- Take about 3 mL of sodium sulphate solution in a test tube.
- In another test tube, take about 3 mL of barium chloride solution.
- Mix the two solutions (Fig. 1.9).
- What do you observe?
A white substance (BaSO4) is formed by the reaction of SO42– and Ba2+. This water insoluble substance is called precipitate. Any reaction that produces a precipitate is called precipitation reaction.
The other product (sodium chloride) remains in solution.