Describe what is observed when magnesium and barium are reacted separately with anexcess of dilute sulfuric acid

When magnesium is reacted with an excess of dilute sulfuric acid, the reaction is vigorous. Magnesium sulfate and hydrogen gas are produced. The equation for this reaction is:

Mg(s) + H2SO4(aq) -> MgSO4(aq) + H2(g)

You will observe effervescence due to the production of hydrogen gas. The solution will also get hot because this is an exothermic reaction.

When barium is reacted with an excess of dilute sulfuric acid, barium sulfate and hydrogen gas are produced. However, barium sulfate is insoluble in water and will precipitate out as a white solid. The equation for this reaction is:

Ba(s) + H2SO4(aq) -> BaSO4(s) + H2(g)

Again, you will observe effervescence due to the production of hydrogen gas. You will also see a white precipitate of barium sulfate forming.