# What volume of a 4.50 M KI stock solution would you use to make 0.455 L of a 1.25 M KI solution?

## Question:

What volume of a {eq}4.50 \, \mathrm{M \; KI} {/eq} stock solution would you use to make {eq}0.455 \, \mathrm{L} {/eq} of a {eq}1.25 \, \mathrm{M \; KI} {/eq} solution?

## Dilution of stock solution:

The stock solutions in the laboratory are present in high concentrations. We have to dilute these solutions as per our requirement. As the concentration of the solution is inversely proportional to the volume of the solution. Therefore water is added to reduce the concentration of the solution.

To make a solution of lower concentration from a solution of higher concentration a known quantity of water is added to the solution.

Given,

{eq}M_1=4.50\,M \\V_1=? \\M_2=1.25\,M \\V_2=0.455\,L {/eq}

Using the formula

{eq}\boxed{M_1\,V_1=M_2\,V_2} \\4.50\,M\times V_1=1.25\,M\times 0.455\,ml \\V_1=0.1263\,L {/eq}

So the volume of water added is = 126.3 ml