Question

A.) If 19.8 grams of an aqueous solution of cobalt(II) sulfate, CoSO4, contains 2.00 grams of cobalt(II) sulfate, what is the percentage by mass of cobalt(II) sulfate in the solution?

B.) An aqueous solution of aluminum chloride, AlCl₃, contains 3.57 grams of aluminum chloride and 17.5 grams of water.
The percentage by mass of aluminum chloride in the solution is

Answer 1

Answer:-

A). Mass of aqueous solution of CoSO₄= 19.8 g

Mass of CoSO₄ = 2.00 g

Mass percentage of CoSO₄ = mass of CoSO₄ x 100/mass of aqueous solution of CoSO₄

=2.00 x 100/ 19.8

= 10.1%

B.) Mass of aluminum Chloride= 3.57 g

mass of water (solvent) = 17.5 g

total mass of solution = mass of aluminum chloride + mass of water

= 17.5+3.57

= 21.07 g

Mass percentage of aluminum chloride= mass of aluminum chloride x 100/ total mass of solution

= 3.57 x 100 / 21.07

= 16.94%