Problem 50P

Determine the amount of potassium chloride in each solution.

(a) 19.7 g of a solution containing 1.08% KCl by mass

(b) 23.2 kg of a solution containing 18.7% KCl by mass

(c) 38 mg of a solution containing 12% KCl by mass

Solution 50P:

Here, we are going to calculate the amount of KCl in each solution by using the formula of mass percent.

Mass percent is defined as

Mass percent (%) =-----(1)

(a) 19.7 g of a solution containing 1.08% KCl by mass

Given that,

Mass percent of solute = 1.08%

Mass of the solution = 19.7 g

From the equation (1)

Mass percent (%) =

Mass of the solute = Mass percent x mass of the solution

= 1.08/100 x 19.7 g

= 0.2127 g

Thus, the amount of potassium chloride in each solution is 0.2127 g

(b) 23.2 kg of a solution containing 18.7% KCl by mass

Given that,

Mass percent of solute = 18.7%

Mass of the solution = 23.2 kg

From the equation (1)

Mass percent (%) =

Mass of the solute = Mass percent x mass of the solution

= x 23.2 kg= 4.338 kg

Thus, the amount of potassium chloride in each solution is 4.338 kg.

(c) 38 mg of a solution containing 12% KCl by mass

Given that,

Mass percent of solute = 12%

Mass of the solution = 38 mg

From the equation (1)

Mass percent (%) =

Mass of the solute = Mass percent x mass of the solution

= x 38mg= 4.56 mg

Thus, the amount of potassium chloride in each solution is 4.56 mg.