2021 - Q1
2021 - Q3
Which of the following features is NOT a characteristic of a state of equilibrium?
A. Equilibrium is achieved in a closed system.
B. Equilibrium position depends on temperature.
C. Equilibrium can be reached from either direction.
D. Equilibrium concentrations of reactants and products are equal.
The following data apply to magnesium fluoride and magnesium chloride dissolving in water at 298 K.
Compare the effects of enthalpy and entropy on the solubility of these salts.
2020 - Q26 (5 marks)
Nitric oxide gas (NO) can be produced from the direct combination of nitrogen gas and oxygen gas in a reversible reaction.
(a) Write the balanced chemical equation for this reaction. ( 1mark)
(b) The energy profile diagram for this reaction is shown.
Explain, using collision theory, how an increase in temperature would affect the value of Keq for this system. Refer to the diagram in your answer. (4 marks)
2021 - Q33 (6 marks)
(a) Calculate delta G for this system at 300 K. (2 marks)
(b) What can be deduced about the system when the temperature is T1, T2 and T3?
Support your answer with reference to the graph. (4 marks)
2022 - Q36 (4marks)
Consider the equilibrium system shown.
H2O(l) <--> H2O(g)
In a laboratory at 23°C, a 100 mL sample of water is held in a beaker and another 100 mL sample is held in a sealed bottle.
Explain the differences in evaporation for these TWO samples. In your answer, consider changes in enthalpy and entropy for this process.