Question

why pure solids and liquids do not have concentration​

Answer 1

pure in the context in here refers to a particular liquid or solid comprising of the same kind of element .

a solid or a liquid without impurities would contain molecules of the same elements and thereby would form bonds and make concentrated compunds.

Answer 2

Pure solids or liquids are excluded from the equilibrium expression because their effective concentrations stay constant throughout the reaction. The concentration of a pure liquid or solid equals its density divided by its molar mass.

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