Chemistry

Concentration of solution
Dilute solution : The solution having small amount of solute is said to have low concentration. it is known as a dilute solution.
Concentrated solution : The solution having a large amount of solute is said to be of high concentration. It is known as a concentrated solution. The concentration of a solution is amount of solute present in a given quantity of the solution. The most common way of expressing the concentration of a solution is the ‘percentage method’.
Example. A 10 per cent solution of common salt means that 10 grams of common salt are present in 100 grams of the solution.
We can calculate the concentration of a solution in terms of mass percentage of solute by using the following formula.
Concentration of Solution =
The mass of solution is equal to the mass of solute plus the mass of solvent. That is :
Mass of solution = Mass of solute + Mass of solvent
So, we can obtain the mass of solution by adding the mass of solute and the mass of solvent.
In the above given example :
Mass of solute (salt) = 10 g
And, Mass of solvent (water) = 90 g
So, Mass of solution = Mass of solvent + Mass of solute = 10 + 90 = 100 g
Now, putting these values of ‘mass of solute’ and ‘mass of solution’ in the above formula, we get :
Concentration of Solution = × 100 = 10 per cent (by mass)