Concentrated Definition (Chemistry)

What Concentrated Means in Chemistry

A concentrated solution contains a large amount of dissolved solute in the solvent.
Steve McAlister / Getty Images

In chemistry, "concentrated" refers to a relatively large quantity of substance present in a unit amount of a mixture. Usually, this means there is a lot of ​a solute dissolved in a given solvent. A concentrated solution contains the maximum amount of solute that can be dissolved. Because solubility depends on temperature, a solution that is concentrated at one temperature may not be concentrated at a higher temperature.

The term may also be used to compare two solutions, as in "this one is more concentrated than that one".

Examples of Concentrated Solutions

12 M HCl is more concentrated than 1 M HCl or 0.1 M HCl. 12 M hydrochloric acid is also called concentrated sulfuric acid because it contains a minimum amount of water.

When you stir salt into water until no more dissolves, you make a concentrated saline solution. Similarly, adding sugar until no more dissolves produces a concentrated sugar solution.

When Concentrated Becomes Confusing

While the concept of concentration is straightforward when a solid solute is dissolved into a liquid solvent, it can be confusing when mixing gases or liquids because it's less clear which substance is the solute and which is the solvent.

Absolute alcohol is considered to be a concentrated alcohol solution because it contains a minimum amount of water.

Oxygen gas is more concentrated in air than carbon dioxide gas. The concentration of both gases could be considered versus the total volume of air or with respect to the "solvent" gas, nitrogen.