What volume of 20 mg/l dye would be required to make 50. ml of .10 mg/l dye?

The volume required is 25 mL.

Explanation:

Given data:

Volume taken form stock solution to make new solution = V1 = ?

Concentration of stock solution = C1 = 20 mg/ L

Concentration of new solution = C2 = 10 mg/ L

Final volume of new solution = V2 = 50 mL

Formula:

C1V1 = C2V2

V1 = C2V2 / C1

Now we will put the values in formula,

V1 = (10 mg /L × 50 mL) / 20 mg / L

V1 = (500 mg /L .mL) / 20mg / L

V1 = 25 mL