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The double replacement reaction

Given

Reaction if Na₂S + HCl

Required

Type of reaction

Solution

The double replacement reaction occurs when there is a displacement of the cations and anions of the reactants involved in the reaction to form two new compounds.

The general formula for this reaction :

AB + CD ⇒ AD + CB

At the bottom of the reaction, it is shown the number of atoms of each compound in the reactants and products which indicates the application of the law of conservation of mass, that the number of atoms in the reactants will be the same as the number of atoms in the product, so the reaction is said to be in a balanced state.