Question

$0.7$ moles of potassium sulphate is allowed to react with $0.9$ moles of barium chloride in aqueous solution. The number of moles of the substance precipitated in the reaction is:

• A. $1.4$ moles of potassium chloride
• B. $0.7$ moles of barium sulphate
• C. $1.6$ moles of potassium chloride
• D. $1.6$ moles of barium sulphate

Answer 1

Answer: (B)

$0.7$ moles of barium sulphate

The balanced chemical reaction is,

$K_{2}S{O}_4+BaC{l}_2\to BaS{O}_4\downarrow +2KCl$

$1$ mole of potassium sulphate reacts with $1$ mole of barium chloride to precipitate $1$ mole of barium sulphate and $2$ moles of potassium chloride is left in the solution.

Hence, in the given situation, sulfate ions are the limiting agents.

So, $0.7$ moles of potassium sulphate reacts with $0.7$ moles of barium chloride to precipitate $0.7$ moles of barium sulphate.