Page 12 - Curriculum Visions Dynamic Book

Preparing hydrogen gas
Hydrogen gas can be produced in
the laboratory by reacting a dilute acid with a metal. The demonstration below uses dilute hydrochloric acid and zinc. Dilute copper sulphate has been added to the hydrochloric acid to speed up the reaction; this is what makes the acid green. The copper does not take part in the reaction; it is a catalyst.
What the apparatus does
Hydrogen is produced by the reaction in the flask. The gas is then led through tubing into a water bath containing a gas jar supported on a beehive shelf. This is the standard way of collecting gases that are not soluble in water. As the gas bubbles through it, the water is displaced but the gas is contained.
At the end of the experiment a cover slip can be placed on the open end of the gas jar while it is still under water, thus sealing the gas in the jar.
Dilute hydrochloric acid and copper sulphate (catalyst)
Gas jar
Hydrogen gas
Beehive shelf to support the gas jar
Zinc metal
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