Chemical Thermodynamics Questions

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[Easy]The standard enthalpy of formation of liquid water is -285.8 kJ/mol and of water vapour is -241.8 kJ/mol. What is the enthalpy of vaporisation of wate...
[Medium]According to the Third Law of Thermodynamics, the absolute entropy of a perfect crystalline substance at absolute zero temperature is zero. Which of t...
[Medium]When 1.00 g of glucose (\(C_6H_{12}O_6\), M = 180 g/mol) is burned in a bomb calorimeter, the temperature rises by 1.48°C. If the heat capacity of the...
[Medium]The enthalpy of vaporisation of benzene is 30.8 kJ/mol at its boiling point of 353 K. What is the entropy change during the vaporisation of 1 mole of ...
[Medium]For the reaction \(2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)\) at 298 K, if \(\Delta \\cup = -196.0\) kJ/mol, what is the value of \(\Delta H\)? (R = 8.3...
[Easy]An ideal gas undergoes reversible adiabatic compression. Which of the following correctly describes the thermodynamic changes during this process?...
[Medium]The lattice enthalpy of NaCl is +788 kJ/mol and the enthalpy of hydration of its ions is -784 kJ/mol. What is the enthalpy of solution of NaCl, and is...
[Easy]Which of the following pairs correctly classifies both quantities as state functions?...
[Medium]For a reaction, \(\Delta G^\circ = -30\) kJ/mol at 298 K. Which of the following is the correct equilibrium constant \(K\) for this reaction? (R = 8.3...
[Easy]At constant pressure, the molar heat capacity of nitrogen gas \((C_p)\) is 29.1 J/mol·K. How much heat is required to raise the temperature of 2 moles...
[Medium]Using bond enthalpy data — C–H: 413 kJ/mol, C=C: 614 kJ/mol, C–C: 347 kJ/mol, H–H: 436 kJ/mol — calculate the enthalpy of hydrogenation of ethylene to...
[Easy]A gas absorbs 450 J of heat and does 120 J of work on the surroundings during an expansion process. What is the change in internal energy of the gas?...
[Medium]One mole of an ideal gas expands isothermally and reversibly at 300 K from a volume of 10 L to 50 L. What is the work done by the gas? (R = 8.314 J/mo...
[Medium]For a reaction at 500 K, \(\Delta H = -40\) kJ/mol and \(\Delta S = -100\) J/mol·K. Which statement correctly describes the spontaneity of this reacti...
[Easy]Which of the following processes is associated with an increase in entropy of the system at constant temperature and pressure?...
[Medium]Given the enthalpies of formation: \(\Delta_f H^\circ(CO_2) = -393.5\) kJ/mol, \(\Delta_f H^\circ(H_2O, l) = -285.8\) kJ/mol, and \(\Delta_f H^\circ(C...
[Medium]According to Trouton's rule, the entropy of vaporization (ΔSvap) for most liquids at their normal boiling point is approximately:...
[Easy]The relation between Cp and Cv for an ideal gas is:...
[Easy]The enthalpy of neutralization of a strong acid by a strong base is approximately:...
[Easy]A Carnot engine operates between 400 K and 300 K. Its efficiency is:...
[Easy]According to the second law of thermodynamics, in an isolated system:...
[Medium]For an ideal gas undergoing isothermal expansion, which statement is correct?...
[Easy]In an adiabatic process, which of the following is true?...
[Medium]Given bond enthalpies: C-H = 413 kJ/mol, Cl-Cl = 242 kJ/mol, C-Cl = 328 kJ/mol, H-Cl = 431 kJ/mol. The enthalpy change for CH₄ + Cl₂ → CH₃Cl + HCl is:...
[Easy]A 50 g sample of water at 20°C is mixed with 50 g of water at 80°C. The final temperature of the mixture is:...
[Easy]The standard enthalpy of formation of an element in its most stable state at 298 K and 1 atm is:...
[Medium]For a reaction to be spontaneous at all temperatures, which condition must be satisfied?...
[Medium]The enthalpy of combustion of methane at 298 K is −890 kJ mol⁻¹. What is the amount of heat released when 5.0 g of methane is completely burnt at this...
[Easy]A system absorbs 250 J of heat and does 150 J of work. The change in internal energy of the system is:...
[Easy]Which of the following processes is accompanied by an increase in entropy?...
[Hard]Given: C(s) + O₂(g) → CO₂(g), ΔH = −394 kJ; 2CO(g) + O₂(g) → 2CO₂(g), ΔH = −566 kJ. The enthalpy of formation of CO(g) is:...