QUESTIONS
1. If the freezing point of the solution is erroneously read 0.2 °C lower than it should be, will
the calculated formula mass of the solute be too high or too low? Explain.
2. How will the freezing point change in this experiment be affected by
a.
The presence of a volatile solute? Explain.
b. Two solutes that react according to the equation A + B \rightarrow C? Explain.
3. If a thermometer is miscalibrated to read 0.5 °C higher that the actual temperature over its
entire scale, will the reported formula mass of the solute be too high or too low?
4. If some solute adheres to the test tube wall in Part B.1, will the freezing point change be
greater than or less than it should be? Explain.
5. If the cyclohexane is initially, but unknowingly, contaminated with a non-reactive, non-
volatile solute, how (if at all) does this affect the reported formula mass of the solute? Why?
6. Explain why the freezing point of a pure solvent remains constant whereas the freezing point
of a solution continues to decrease with time (Figure 2).
