Description: This activity studies the reaction between metals and acids by dropping some zinc granules into dilute hydrochloric acid and dilute sulphuric acid. In each case, a gas is released and when this gas is tested with a matchstick flame, we get a characteristic popping sound and see that the matchstick burns more brightly. This indicates that the gas produced is hydrogen. Zinc forms the salt zinc sulphate with sulphuric acid and zinc chloride with hydrochloric acid and releases hydrogen gas in both cases. In general, a metal reacts with an acid to form a salt and releases hydrogen gas.