Question

A potassium bromide solution is 7.55% potassium bromide by mass and its density is 1.03 g/ml. part a what mass of potassium bromide is contained in 35.8 ml of the solution?

Answer 1

Answer : The mass of potassium bromide contained in 35.8 ml of solution is, 2.784 grams.

Explanation : Given,

Density of solution = 1.03 g/mole

7.55 % potassium bromide by mass means that 7.55 gram of potassium bromide present in 100 grams of solution. So,

Mass of potassium bromide = 7.55 g

Mass of solution = 100 g

First we  have to calculate the volume of solution.

$\text{Volume of solution}=\frac{\text{Mass of solution}}{\text{Density of solution}}=\frac{100g}{1.03g/mole}=97.08ml$

Now we have to calculate the mass of potassium bromide in 35.8 ml of the solution.

As, 97.08 ml of solution present in 7.55 gram of potassium bromide

So, 35.8 ml of solution present in $\frac{7.55}{97.08}\times 35.8=2.784$ gram of potassium bromide

Therefore, the mass of potassium bromide contained in 35.8 ml of solution is, 2.784 grams.

Answer 2

67.234 percent is correct