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Acids and alkalis - EdexcelReactions of acids

Indicators are used to determine if a solution is acidic or alkaline. Acids react with metals, bases and carbonates to produce salts. Neutralisation is the reaction between an acid and a base.

Part of Chemistry (Single Science)Chemical changes

Reactions of acids

take part in reactions in which are produced. In these reactions, the salt is formed by replacing the hydrogen in the acids with metal ions or ammonium ions.

Reactions with metals

A salt and hydrogen are produced when acids react with .

In general:

acid + metal 鈫 salt + hydrogen

For example:

hydrochloric acid + magnesium 鈫 magnesium chloride + hydrogen

2HCl(aq) + Mg(s) 鈫 MgCl2(aq) + H2(g)

Question

Hydrogen is collected in a test tube during the reaction between magnesium and hydrochloric acid. Describe the laboratory test for hydrogen.

Reactions with metal oxides

A salt and water are produced when acids react with metal . Metal oxides are , because they neutralise acids.

In general:

acid + metal oxide 鈫 salt + water

For example:

sulfuric acid + copper oxide 鈫 copper sulfate + water

H2SO4(aq) + CuO(s) 鈫 CuSO4(aq) + H2O(l)

Reactions with metal hydroxides

A salt and water are produced when acids react with metal hydroxides. Metal hydroxides are bases because they neutralise acids.

In general:

acid + metal hydroxide 鈫 salt + water

For example:

nitric acid + sodium hydroxide 鈫 sodium nitrate + water

HNO3(aq) + NaOH(s) 鈫 NaNO3(aq) + H2O(l)

Reactions with carbonates

A salt, water and carbon dioxide are produced when acids react with carbonates.

In general:

acid + carbonate 鈫 salt + water + carbon dioxide

For example:

hydrochloric acid + copper carbonate 鈫 copper chloride + water + carbon dioxide

2HCl(aq) + CuCO3(s) 鈫 CuCl2(aq) + H2O(l) + CO2(g)

Question

Carbon dioxide is given off during the reaction between copper carbonate and hydrochloric acid. Describe the laboratory test for carbon dioxide.