Question

Name the gas usually liberated when a dilute acid reacts with a metal what happens when a burning candle is brought near this gas

Answer 1

Dear student
When a metal reacts with a dilute acid hydrogen gas is released . For ex when Mg reacts with dil.HCl, we get MgCl₂ and Hydrogen gas is released.
Mg(s) + 2HCl(aq) $\to$ MgCl₂(aq) + H₂(g)
When a burning candle is brought near the test tube a pop sound is heard , which proves that Hydrogen gas is released.

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