Precipitate

Definition

A precipitate is a solid that forms and separates from a liquid mixture during a chemical reaction. It often occurs when two aqueous solutions react to form an insoluble product.

5 Must Know Facts For Your Next Test

1. A precipitate forms when the product of a reaction is insoluble in the solvent used.
2. The formation of a precipitate is often indicated by cloudiness or solid particles settling at the bottom of the solution.
3. Common types of reactions that produce precipitates are double displacement reactions.
4. The solubility rules help predict whether a precipitate will form in a given reaction.
5. The balanced equation for a reaction can be used to determine the amount of precipitate formed using stoichiometric calculations.

Review Questions

• What visual evidence indicates that a precipitate has formed in a chemical reaction?
• Which type of chemical reaction often results in the formation of a precipitate?
• How can you predict if a precipitate will form when two solutions are mixed?

Related terms

Solubility:

The ability of a substance to dissolve in a solvent to form a homogeneous mixture.

Double Displacement Reaction: A type of chemical reaction where parts of two compounds swap places to form two new compounds, one of which may be an insoluble precipitate.

Stoichiometry:

The calculation of reactants and products in chemical reactions using balanced equations.