Question

How many mL of water would you add to 32 mL of 0.62 M ammonium chloride stock solution to make a 0.3 M solution?

Answer 1

0.62 M x (32/x) = 0.3 M
x = total voume so x-32 will be how much you must add.

Answer 2

I would have .62 mols in a liter
so I have .62 (.032 ) = .01984 mols

.01984 mols /x liters = 0.3 mols/1 liter
x = .01984/.3 = .06613 liters = 66.13 mL
so add 66 -32 = 34 mL of water

Answer 3

How many mL of water would you add to 32 mL of 0.62 M ammonium chloride stock solution to make a 0.3 M solution? >>
Another method. You are diluting it .62/.3 = 2.06 times. That means one part original, and then add 1.06 parts water.
if one part is 32ml, then 1.06 parts is 33.9 ml of water