Originally Posted by boobunkin1
I need to dilute a 70 % solution to a 25 % solution. lets say I have 100 cc of the 70% solution. how many cc to I add to make it into a 25 % solution. any help will be appreciated.

100 ml of 70% solution contains 70 ml of solute liquid
70 ml =0.25 x x =total ml of 25% solute =280 ml so 180 ml of solvent must be added to the given 100ml