Two aqueous are prepared: 1.00 m Na₂CO₃ and 1.00 m LiCl. Which of the following statements is true? A) The Na₂CO₃ solution has a higher osmotic pressure and higher vapor pressure than the LiCl solution. B) The Na₂CO₃ solution has a higher osmotic pressure and higher boiling point than the LiCl solution. C) The Na₂CO₃ solution has a lower osmotic pressure and lower vapor pressure than the LiCI solution. D) The Na₂CO₃ solution has a lower osmotic pressure and higher boiling point than the LiCl solution. E) None of these choices is correct.

Question

Quizplus · Accepted Answer

Both solutions are strong electrolytes, so we need to use the van't Hoff factor to calculate their osmotic pressure. Na₂CO₃: i = 3 LiCl: i = 2 Since both solutions are 1.00 m, they have the same concentration. However, the Na₂CO₃ has a higher van't Hoff factor, which means it will have a higher osmotic pressure. Also, according to the boiling point elevation equation, ΔTb = Kb x m x i, where Kb is the molal boiling point elevation constant and m is the molality of the solution. Since both solutions are 1.00 m, they have the same molality, but the Na₂CO₃ has a higher van't Hoff factor, which means it will have a higher boiling point elevation. Therefore, the Na₂CO₃ solution has a higher osmotic pressure and higher boiling point than the LiCl solution.

Two Aqueous Are Prepared: 1