[INSERT MS_CI_07_ima]

The reaction of acids with metals is another useful type of reaction. The image above shows the reaction of iron in dilute hydrochloric acid.

Which metals react with acids? What are the products?

Reactive metals, ie metals above hydrogen in the reactivity series, react with dilute acids to form a metal salt and give off hydrogen gas.

metal + acid _↓ hydrogen + metal salt

What is the word equation for the following examples? (As before, think about the usual product of this type of reaction and then what is left as a salt.)

calcium with hydrochloric acid?

calcium + hydrochloric acid _↓ hydrogen + calcium chloride

iron with nitric acid?

iron + nitric acid _↓ hydrogen + iron nitrate

magnesium with sulfuric acid?

magnesium + sulfuric acid _↓ hydrogen + magnesium sulfate

copper with (dilute) hydrochloric acid?

No reaction (copper is below hydrogen in the reactivity series).

How might you show students that the other product of the reaction of metals with acids is indeed hydrogen?

Hydrogen fizzes from solution and can be tested by the usual lighted splint method giving the distinctive 'pop' sound. If a metal reacts with an acid then hydrogen gas will always be given off to leave a salt.

More support for teaching about the reactivity series and redox chemistry is available by subscribing to the Redox course. This small scale or 'microscale' practical activity shows the reaction of various metals in acid.