Dilution refers to a drop in the pH of a chemical which can be a gas, vapour or solution. It involves the process of decreasing the concentration of a solute in the solution normally by mixing with the solvent. To dilute a solution add more solvent without the addition of more solute. Mix the resulting solution thoroughly to ensure that all parts of the solution are even.
For example, if 10 grams of salt is dissolved in 1 litre of water, it has a particular salt concentration. By adding 1 litre of water to this solution, the salt concentration is reduced. The dilute solution still has 10 grams of salt.
To prepare a fixed amount of dilute solution, we have a formula
C1V1 = C2V2
V1 denotes the Volume of stock solution needed to make the new solution
V2 is the final volume of the solution
C1 = Concentration of stock solution
C2 = Final concentration of stock solution
A chemist needs 1.5M hydrochloric acid for a reaction. The solution available is 6M of HCl. What is the volume of 6M HCl to be diluted to obtain 5L of 1.5M HCl?
Initial concentration of HCl is 6M
Final concentration of HCl is 1.5M
Final volume of solution is 5L
The initial volume needs to be found.
Substituting the values, we get
Vi = 1.5 x 5.0 / 6
= 1.3 L