2021 - Q1
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2021 - Q3
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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.
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The following data apply to magnesium fluoride and magnesium chloride dissolving in water at 298 K.
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Compare the effects of enthalpy and entropy on the solubility of these salts.
2020 - Q26 (5 marks)
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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)
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(b) The energy profile diagram for this reaction is shown.
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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)
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(a) Calculate delta G for this system at 300 K. (2 marks)
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(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)
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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.