posted by Muhammad .
1000g of a 55%(mass percentage) nitric acid solution is to be diluted to 20%(mass percentage) nitric acid solution.how many liters of water should be added to the starting solution?
you want to dilute it by a factor of 55/20=2.75 which means, you add 1.75 parts of water, and 1 part original.
one part: 1000g
water: 1.75 liters added.
Now check. You have 550g of HNO3 in 2.750kg solution, which is 550/2750 percent, or 20 percent.