Question

A potassium bromide solution is 8.34% potassium bromide by mass and its density is 1.03 g/ml. what mass of potassium bromide is contained in 44.8 ml of the solution?

Answer 1

Answer:-  3.84 grams

Solution:-  Volume of the sample is 44.8 mL and the density is 1.03 gram per mL.

From the density and volume we calculate the mass as:

mass = volume*density

$44.8mL(\frac{1.03g}{mL})$

= 46.1 g

From given info, potassium bromide solution is 8.34% potassium bromide by mass. It means if we have 100 grams of the solution then 8.34 grams of potassium bromide is present in. We need to calculate how many grams of potassium bromide are present in 46.1 grams of the solution.

The calculations could easily be done using dimensional analysis as:

$46.1gSolution(\frac{8.34gKBr}{100gSolution})$

= 3.84 g KBr

Hence, 3.84 grams of KBr are present in 44.8 mL of the solution.