# Expression of concentration of solutions of solids in liquids

The concentration of a solution is a measure of how much solute is dissolved in a given amount of solvent or solution.

A concentrated solution is one in which the amount of dissolved solute is typically high.

Expression of concentration means, concentrated solution is one that has a relatively large amount of dissolved solute

and dilute solution is one that has a relatively small amount of dissolved solute.

The diluted or concentrated solution is a qualitative means of expressing the solutionâ€™s concentration.

## Mass percentage

The mass percentage of a component in a given solution is the mass of the component per 100g of the solution.

if WA is the mass of the component A, WB is the mass of the component B in a solution.

Then, Mass Percentage of A in solution = WA/(WA +WB) * 100

### Volume percentage

This unit is used in case of a liquid dissolved in another liquid. The volume percentage is defined as the volume of the solute per 100 parts by volume of solution.

Volume Percentage of A in solution = VA/Vsol* 100

Strength of a solution is defined as the amount of the solute in gms, present in one litre of the solution. It is expressed as gL-1.

Strength = Mass of Solution in g/Volume in solution in Liters

### Molarity

Molarity of a solution is defined as the number of moles of solute dissolved per litre of solution.

Molarity = No of Moles of Solution/Volume of solution in Liters

If 'a' is the weight of the solute (in gms) present in VCC volume of the solution.

Molarity = a/Mole of Mass * 1000 /V

### Solutions of solids in liquids

The solubility of a solute is defined as the amount of solute dissolved in 100g of solvent in a saturated solution at a certain temperature.

In the case of exothermic compounds, solubility is inversely related to temperature (KOH, CaO, Ca(OH)2, M2CO3, M2SO4, etc.)

In the case of endothermic compounds solubility is directly proportional to temperature (NaCl, KNO3, NaNO3, glucose, etc).