Physical Chemistry 2.pdf - OER@AVU - African Virtual University

African Virtual University
IX. Teaching and learning activities
9.1 Pre-assessment
Pre-assessment on the understanding of fundamental principles: for solutions and
colloids, phase equilibria, electrochemistry and nuclear chemistry.
Rationale
For the learner to complete this module successfully, prior requisite knowledge is
necessary. This pre-assessment allows the learner to know how prepared there are
for the topics likely to be encountered. The questions are an evaluation of knowledge
previously acquired such as principles of solutions, balancing redox reactions and
thermodynamics. These questions relate to concepts that are key to understanding
solutions, phase equilibria, reactions that involve charge transfer and subatomic level
reactions.
Questions
1. Which of the following substances exerts the highest pressure? Give reason(s)
for your answer.
(a) 1 mole N 2 at 273 K in 11.2 dm −3
(b) 1 mole N 2 at 300 K in 22.4 dm −3
(c) 1 mole H 2 O at 300 K in 1 dm −3
(d) 1 mole C 4 H 10 at its normal b. pt
2. How would you expect the substances given below to behaviour in the solvents
indicated i.e. low or high solubility?
(a) HCl in H O 2
(b) HF in H O 2
(c) S in H O.
8 2
(d) NaNO in hexane, C H 3 6 14
3. Consider the following two sets of mixtures (a) water mixed with methanol,
obeys Raoults law and (b) water mixed propan-1-ol, which forms an azeotropic
mixture. With the information given draw suitable schematic diagrams to illustrate
their behaviour using a vapour pressure/composition curves.