Arun added to a few pieces of granulated zinc metal to 2 𝑚𝑙 of sodium hydroxide solution taken in a test tube. He warmed the test tube which resulted in the evolution of a gas. This gas was bubbled through a soap solution before testing. Write the equation of the chemical reaction involved and the test to detect the gas. Name the gas which will be evolved when the same metal reacts with a dilute solution of a strong acid.