Reactions of Dilute Acids with Metals

General Knowledge:

When dilute acids react with metals they produce salt and hydrogen gas.
This reaction only happens with reactive metals including magnesium, zinc, and iron, but not with less reactive metals such as copper or silver.
The specific salt produced in the reaction depends on the type of acid and metal used.

Reaction with Hydrochloric Acid:

Reaction of a metal with hydrochloric acid always produces a type of chloride salt.
For instance, if zinc is reacted with hydrochloric acid, the equation becomes:
Zn (s) + 2HCl (aq) -> ZnCl2 (aq) + H2 (g)
The hydrogen gas given off can be tested using a lit splint, which should create a squeaky pop sound.

Reaction with Sulfuric Acid:

When a metal reacts with sulfuric acid, a type of sulphate salt is produced.
For example, when magnesium is reacted with sulfuric acid, the equation is:
Mg (s) + H2SO4 (aq) -> MgSO4 (aq) + H2 (g)
The test for hydrogen gas remains the same, using a lit splint to check for the pop sound.

Reaction with Nitric Acid:

Nitric acid is a bit peculiar as it produces oxides of nitrogen instead of hydrogen when it reacts with metals.
Because of this, nitric acid is not typically used in testing for gas produced in reactions of acids with metals.
An example reaction with zinc:
Zn (s) + 2HNO3 (aq) -> Zn(NO3)2 (aq) + 2NO2 (g) + 2H2O (l)

Remember:
More reactive metals, like potassium (K), sodium (Na) and calcium (Ca) react vigorously with acids, and it’s dangerous to carry out these reactions.