How much water would I need to add in order to dilute 200mL of a 5 M solution down to 2 M?
Didn't I do one like this for you yesterday.
c1v1 = c2v2
c = concn
v = volume
5*200 = 2*mL
mL = total volume.
To find out how much water you need to add to dilute a solution, you can use the dilution formula:
C1V1 = C2V2
Where:
C1 = initial concentration
V1 = initial volume
C2 = final concentration
V2 = final volume
In your case:
C1 = 5 M (initial concentration)
V1 = 200 mL (initial volume)
C2 = 2 M (final concentration)
V2 = ??? (final volume, which is what we want to find)
Now we can plug in these values into the formula:
(5 M) (200 mL) = (2 M) (V2)
Simplifying the equation:
1000 = 2 V2
Dividing both sides by 2:
V2 = 500 mL
Therefore, you would need to add 500 mL of water to the 200 mL of the 5 M solution in order to dilute it down to a 2 M solution.