Question

A mass of 0.750 g calcium chloride is diluted with 975 g H2O. What is the chloride ion concentration (in ppm)? Show all calculations and report your answer to the correct number of sig figs.

Answer 1

Mass of Calcium chloride (CaCl₂) = 0.750 g.

Molar mass of Calcium chloride = 111 g/mol.

So , in 111 g calcium chloride mass of chloride ion = 71 g.

Then, in 0.750 g Calcium chloride mass of chloride ion

= 0.750 × { }

= 0.480 g.

Now,

Concentration of chloride ion in ppm.

=

= 492 ppm. (3 significant figures) .