Question

How can you prepare 100.0 ml of 0.400 m CaCl2 from a stock solution of 2.00 m CaCl2.

Answer 1

100.0ml*0.400m =xml *2.00m
x=100.0*0.400/2.00= 20 ml 2.0 m CaCl2

you need to take 20 ml 2.0 m CaCl2 and dilute it with water up to 100.0 ml

Answer 2

Use the dilution equation to calculate the volume of the stock solution required.

Stock solution volume required is 20.0 mL.

Add water to concentrated solution to reach the desired volume.

The volume of water to add is 80.0 mL.