What is a double decomposition reaction? How many types of double decomposition reaction do you know of? Give one example of each.
A reaction in which two compounds react to form two other compounds by mutual exchange of atoms or group of atoms is called double displacement reaction. There are two types of double displacement reaction.
(a) Precipitation reaction: In this reaction, two compounds react in their aqueous state to form an insoluble product, which appears in the form of a precipitate. For example, aqueous sodium chloride and silver nitrate react to form a white precipitate of silver chloride.
NaCl + AgNO3 → AgCl↓ + NaNO3
Sodium Silver Silver Sodium
chloride nitrate chloride nitrate
(b) Neutralisation reaction: When a base and an acid react, they exchange their ions and form compounds called salt, water and sometimes a gas. For example, hydrochloric acid reacts with potassium hydroxide to form potassium chloride (salt) and water.
HCl + KOH → KCl + H2O
Hydrochloric Potassium Potassium Water
acid hydroxide chloride
A reaction in which two compounds react to form two other compounds by mutual exchange of atoms or group of atoms is called double displacement reaction. There are two types of double displacement reaction.
(a) Precipitation reaction: In this reaction, two compounds react in their aqueous state to form an insoluble product, which appears in the form of a precipitate. For example, aqueous sodium chloride and silver nitrate react to form a white precipitate of silver chloride.
NaCl + AgNO3 → AgCl↓ + NaNO3
Sodium Silver Silver Sodium
chloride nitrate chloride nitrate
(b) Neutralisation reaction: When a base and an acid react, they exchange their ions and form compounds called salt, water and sometimes a gas. For example, hydrochloric acid reacts with potassium hydroxide to form potassium chloride (salt) and water.
HCl + KOH → KCl + H2O
Hydrochloric Potassium Potassium Water
acid hydroxide chloride
