Chemical Thermodynamics - SS2 Chemistry Past Questions and Answers - page 1
Which of the following statements is true according to the First Law of Thermodynamics?
Energy can be created or destroyed.
The total energy of a closed system remains constant.
Energy flows spontaneously from a cooler object to a hotter object.
The entropy of a system always increases.
The Second Law of Thermodynamics states that:
Energy is conserved in all physical and chemical processes.
Heat always flows from a higher temperature object to a lower temperature object.
The entropy of a system approaches zero as its temperature approaches absolute zero.
It is impossible to construct a device that operates in a cycle and extracts heat from a single reservoir to produce work.
The Third Law of Thermodynamics states that:
Energy is conserved in all physical and chemical processes.
The entropy of a pure crystalline substance is zero at absolute zero temperature.
The total energy of a closed system remains constant.
The entropy of a system always increases.
The change in internal energy (ΔU) of a system is given by:
ΔU = q - w
ΔU = q + w
ΔU = q/T
ΔU = -q - w
The equation ΔS = qrev/T relates which of the following quantities?
Change in internal energy and temperature
Change in entropy and heat transfer
Change in entropy and work done
Change in temperature and heat transfer
Discuss two laws of thermodynamics. Explain the concepts and implications of both laws, and provide examples illustrating their application.
Which of the following statements best describes enthalpy?
It represents the disorder or randomness of a system.
It measures the heat content of a system at constant pressure.
It determines the direction of a spontaneous reaction.
It quantifies the free energy change of a reaction.
The standard enthalpy change of a reaction is defined as:
The change in enthalpy of the reaction when reactants are in their standard states.
The enthalpy change of a reaction that occurs at standard temperature and pressure.
The difference in enthalpy between products and reactants of a reaction.
The enthalpy change of a reaction when one mole of a compound is formed from its elements in their standard states.
Which of the following is an example of an exothermic process?
Melting of ice cubes at room temperature.
Dissolution of an ionic compound in water.
Evaporation of water.
Boiling of water
Entropy is a measure of:
The heat content of a system.
The disorder or randomness of a system.
The enthalpy change of a reaction.
The free energy change of a reaction.