When magnesium is added to hydrochloric acid, a gas is formed. Explain what happens in the reaction, how the gas is collected and how it could be tested to prove what it is.

Explained below.

Explanation:

Formula when magnesium reacts with hydrochloric acid is given by;

Mg(s) + 2HCl(aq) = MgCl2(aq) + H2(g)

So, from the equation, we can see that the gas formed is hydrogen.

This hydrogen gas is collected by a method known as water displacement.

This gas can be tested for by holding a burning splint near to the top of the test container. The resulting effect should be a high pitched pop sound because the hydrogen gas will react with the oxygen gas in the air to result in a small explosion.

one negative thing it that it can kill water animals. another negative thing is it can cause the destruction of ecosystem. one way water pollution can be reduced is to conserve energy.