V 2 = volume of glassware to contain diluted solution ; V 1 = volume you will transfer (from stock solution) to the glassware to contain diluted solution M 2 = concentration desired ; M 1 = concentration you have a. If you are given a solution of 2 M CoCl 2 •(H 2 O) 6 , and you want a solution of 1 M to be contained in a 10 mL flask, what is V 1 ? b. So you will transfer V 1 mL of the M 1 solution to the (V 2 = 10 mL) flask, dilute to the V 2 mL mark, and then you will have a concentration of M 2 . What is M 2 ? c. You will repeat this serially for several dilutions but starting the final dilution concentration of the last step for the next step (for example: M 2 in part B becomes M 1 for the next step). Solution initial M1 and final M2 initial V1 and final V2 M1V1 = M2V2 a) require 10 ml of 1M solution from 2 M CoCl2(H2)6 stock V1 needed = M2V2/M1 = 1 M x 10 ml/2 M = 5 ml b. 5 ml of 1 M solution (a) diluted to 10 ml M2 = M1V1/V2 = 1 M x 5 ml/10 ml = 0.5 M .

1. V 2 = volume of glassware to contain diluted solution ; V 1 = volume you will transfer (from
stock solution) to the glassware to contain diluted solution
M 2 = concentration desired ; M 1 = concentration you have
a. If you are given a solution of 2 M CoCl 2 •(H 2 O) 6 , and you want a solution of 1 M to be
contained in a 10 mL flask, what is V 1 ?
b. So you will transfer V 1 mL of the M 1 solution to the (V 2 = 10 mL) flask, dilute to the V 2 mL
mark, and then you will have a concentration of M 2 . What is M 2 ?
c. You will repeat this serially for several dilutions but starting the final dilution concentration of
the last step for the next step (for example: M 2 in part B becomes M 1 for the next step).
Solution
initial M1 and final M2
initial V1 and final V2
M1V1 = M2V2
a) require 10 ml of 1M solution from 2 M CoCl2(H2)6 stock
V1 needed = M2V2/M1
= 1 M x 10 ml/2 M
= 5 ml
b. 5 ml of 1 M solution (a) diluted to 10 ml
M2 = M1V1/V2
= 1 M x 5 ml/10 ml

2. = 0.5 M