Question

An ammonia and water mixture fills a five-gallon container. Eighty percent of the mixture is ammonia but some of the mixture will be drained and replaced with pure water. If a five-gallon mixture of fifty percent ammonia is desired, how many quarts of the mixture need to be drained before the water is added

Answer 1

The volume of the 80% ammonia that is to be drained before water is added is 7.5 quartz

Explanation:

The volume of the ammonia and water mixture = 5 gallons

The percentage of ammonia in the mixture = 80%

The volume of ammonia desired = 5 gallons

The percentage concentration of ammonia desired = 50%

The diluting solution = Pure water

The measure of 4 quarts = 1 gallon

Therefore, we have, by equivalence solutions;

80% × x gallon = 50% × 5 gallons

x gallon = 50% × 5 gallons/(80%) = 3.125 gallons

x = 3.125 gallons

The volume of the 80% ammonia that is to be drained = 5 gallons - 3.125 gallons = 1.875 gallons

4 quarts = 1 gallon

1 gallon = 4 quarts

∴ 1.875 gallons = 4 × 1.875 quartz = 7.5 quartz

The volume of the 80% ammonia that is to be drained before water is added = 7.5 quartz