passwella.
Menu

JAMB Chemistry 1985 Question 11

Question 11

Solubility and Solutions

Figure 2 represents the solubility curves of two salts, X and Y, in water. If the molar mass of X is 36 g, the number of moles of X dissolved at 343 K is

Diagram for this question
  1. A.0.2 moles
  2. B.0.7 moles
  3. C.1.5 moles
  4. D.2.0 moles
  5. E.3.0 moles
Show the answer and explanation

Answer: D (2.0 moles)

Explanation

From the graph, about 70 g of X dissolves in 100 g of water at 343 K. Moles = 70/36 ≈ 1.9, which is closest to 2.0 moles.