Difficulty: Medium
Average Score: 64%
Entry Exam
A student conducts an experiment where they dissolve 1 g each of several substances in 50 mL of water. They have 12 identical plastic cups of water and place 1 g of salt into three of the cups, 1 g of sugar into three of the cups, and 1 g of baking soda into three of the cups. The three remaining cups contain only water. All the cups are put in a freezer, and the temperature of the solution in each cup is recorded every 15 minutes for 4 hours. What question is the student most likely investigating?
Correct answer
A
Rationale
The student is most likely investigating the effect of different concentrations of solutes (salt, sugar, baking soda) on the freezing point of water. By monitoring the temperature changes during freezing, the student can observe how each solute affects the freezing point. This experiment helps understand the concept of colligative properties, where the presence of solutes lowers the freezing point of a solvent like water. Therefore, the correct answer is A: 'What effect do different concentrations of solute have on the freezing point of water?'