What does concentration refer to in a solution?

Concentration in the context of a solution refers to the amount of solute present relative to the volume of the solvent or the total solution. It is a measure of how much of a substance (the solute) is dissolved in a given quantity of solvent. This concept is essential in chemistry because it influences the properties of the solution, such as its reactivity, boiling point, and osmotic pressure.

When discussing concentration, it can be expressed in various ways, such as molarity (moles of solute per liter of solution), mass percent, or volume percent. Understanding concentration is crucial in formulating solutions for experiments, medical dosing, and many industrial applications.

Temperature, physical state, and the total volume of the solution are not direct measures of how much solute is present in the solution and thus do not define concentration.