Ho w much water would you need to add to 500 mL of a 0.3 M calcium nitrate solution to make
the
solution
0.1
M?
A.
1.0
L
B.
0.50
L
C.
1.5
L
D.
0.25
L
E.
3.0
L
The answer is A but I cannot figure it out.
Use the dilution formula.
mL1 x M1 = mL2 x M2
500 mL x 0.3M = mL2 x 0.1M
mL2 = you do it.
mL2 is the final volume of the solution. You want to know how much water to add. Assuming volumes are additive, you would need to add the difference between mL2 and 500 mL.
An easier way to do this is to note you have 0.3M and you want to make 0.1M. So you want to dilute it a factor of 3 times. 3*500 = 1500 final volume. So you add 1500-500 = ?