Question

What mass of Calcium Bromide (below) is needed to make 0.500 L of
0.554 M solution? (hint: find moles first, then convert to grams)

Answer 1

55.36 is the mass of Calcium Bromide is needed to make 0.500 L of  0.554 M solution.

Explanation:

Data given:

mass of Ca$Br_{2}$ = ?

molarity of the calcium bromide solution = 0.554 M

Volume of the calcium bromide solution= 0.5 L

First the moles of calcium bromide is calculated as:

molarity = $\frac{number of moles}{volume in litres}$

number of moles = 0.554 x 0.5

number of moles = 0.277 moles of calcium bromide

atomic mass of calcium bromide = 199.89 grams/mole

mass = atomic mass x number of moles

mass of calcium bromide = 199.89 x 0.277

                                           = 55.36 grams

mass of calcium bromide required is 55.36 grams to make solution of 0.554 M in a solution of 0.5 litres.