Testing carbon dioxide with limewater IMG 0422

High School Chemistry
Video clip with sound, portrait orientation
Using limewater to test for carbon dioxide
Carbon dioxide is produced by reacting calcium carbonate with dilute hydrochloric acid in a test-tube.
The gas is sampled using a plastic dropping pipette and bubbled through limewater.
Limewater is a solution of calcium hydroxide, which is sparingly soluble in water.
The limewater produces a white precipitate of calcium carbonate on reacting with carbon dioxide gas.