You have 2 L of a 10M stock solution. You need to make 500 mL of a 2 M solution. What volume would you need to add to the new solution?
To calculate the volume needed to add to the new solution, we can use the formula:
M1V1 = M2V2
where:
M1 = initial concentration
V1 = initial volume
M2 = final concentration
V2 = final volume
We have:
M1 = 10M
V1 = 2 L
M2 = 2 M
V2 = 0.5 L
Using the formula:
(10M)(2 L) = (2 M)(V2)
20 = 2V2
V2 = 10 L
Therefore, you would need to add 10 L of water to the new solution to make a 500 mL of a 2 M solution.