Question

You can practice converting between the mass of a solution and mass of solute when the mass percent concentration of a solution is known. The concentration of the KCN solution given in Part A corresponds to a mass percent of 0.480 %. What mass of a 0.480 % KCN solution contains 697 mg of KCN? Express the mass to three significant figures and include the appropriate units. View Available Hint(s)

Answer 1

Answer:

145 grams of a 0.480 % KCN solution contains 697 mg of KCN.

Explanation:

w/w % : The percentage mass or fraction is mass of the of solute present in 100 grams of the solution.

$w/w\%=\frac{\text{Mass of solute}}{\text{Mass of solution}}\times 100$

given =  w/w% = 0.480 %

Mass of solute that KCN = 697 mg = 0.697 g

(1 mg = 0.001 g)

Mass of the solution = ? = x

$0.480\%=\frac{0.697 g}{x}\times 100$

$x=\frac{0.697 g}{0.480}\times 100$

x = 145.21 g ≈ 145 g

145 grams of a 0.480 % KCN solution contains 697 mg of KCN.