Waec Model Questions Vol1 2025 Chemistry Question 3

A student is investigating the properties of ionic compounds. She prepares a solution of sodium chloride (NaCl) in water and performs a conductivity test. She also prepares a solution of glucose (C6H12O6) in water and conducts a similar test. (a) Describe the expected observations for each solution regarding conductivity and explain the underlying reasons for these observations. (b) The student then decides to evaporate the water from the sodium chloride solution to obtain the solid salt. Explain the process she would follow and the changes that occur during evaporation. (c) If the student were to repeat the experiment using potassium chloride (KCl) instead of sodium chloride, predict whether the conductivity observations would change and justify your answer.