List of top Physical Chemistry Questions on Thermodynamics

At a constant pressure, the entropy of mixing of 1 mole of oxygen with 3 moles of nitrogen at 25 $^\circ$C is _ _ _ J K$^{-1}$. (rounded off to two decimal places)
A system consists of 110 particlesEach particle can have only two non-degenerate energy states $\epsilon_1$ and $\epsilon_2$ with $\epsilon_2 > \epsilon_1$The energy difference between these two states is 0.10 eVThe temperature at which only 10 particles of the system will be present in the energy state $\epsilon_2$ is _ _ _ K. (rounded off to two decimal places)
For the transformation of 1 mole of an ideal gas from an initial temperature of 27$^\circ$C and an initial pressure of 1 atm to a final temperature of 327$^\circ$C and a final pressure of 17 atm, the change in enthalpy, $\Delta H$, is _ _ _ kJ
Identify the reaction for which, at equilibrium, a change in the volume of the closed reaction vessel at a constant temperature will not affect the extent of the reaction
The enthalpy change for the reaction
C(𝑔) +\( \frac{1}{2}\) O2(𝑔)β†’CO(𝑔) is _______ kJ per mole of CO(𝑔) produced. 
(rounded off to one decimal place) 
[Given: 
C(𝑔)+O2(𝑔) β†’ CO2(𝑔), Ξ”Hrxn = βˆ’393.5 kJ per mole of CO2(𝑔) produced 
CO2(𝑔) β†’ CO(𝑔) +\( \frac{1}{2}\) O2(𝑔), Ξ”Hrxn = 283.0 kJ per mole of CO(𝑔) produced]
A system undergoes one clockwise cycle from point X back to point X as shown in the figure below:
clockwise cycle-point X back to point X
The correct statement about this process is
The correct relation(s) for an ideal gas in a closed system is/are
Consider the following reaction:
2 C6H6+15 O2β†’12 CO2+6 H2O \(Ξ”_r𝐻^0_{298}\) =βˆ’3120 kJ molβˆ’1.
A closed system initially contains 5 moles of benzene and 25 moles of oxygen under standard conditions at 298 K. The reaction was stopped when 17.5 moles of oxygen is left. The amount of heat evolved during the reaction is____kJ. 
(round off to the nearest integer)
In the Born-Haber cycle, the heat of formation of CuCl is ______ kJ/mol.
[Given: Heat of atomization of Cu = +338 kJ/mol, 
Ionization energy of Cu = +746 kJ/mol, 
Heat of atomization of Cl2 = +121 kJ/mol, 
Electron affinity of Cl = βˆ’349 kJ/mol, and 
Lattice energy of CuCl = βˆ’973 kJ/mol] 
(round off to the nearest integer)
The volume of 2.0 mol of an ideal gas is reduced to half isothermally at 300 K in a closed system. The value of Ξ”G is_____ kJ.
[Given: R=8.314 J mol-1 K-1 ] 
(round off to two decimal places)
The standard Gibbs free energy change for the reaction
$H_2O (g) β†’ H_2 (g) + Β½ O_2(g)$ at 2500 K is $+118 kJ mol^{-1}$
The equilibrium constant for the reaction is
[Given: $R= 8.314 J K^{-1} mol^{-1}$]
Among the following, the reaction(s) that favor(s) the formation of the products at 25 Β°C is/are
The reaction involve(s)
The reaction involve(s)
For an N-atom nonlinear polyatomic gas, the constant volume molar heat capacity Cv,m has the expected value of 3(N-1)R, based on the principle of equipartition of energy. The correct statement(s) about the measured value of Cv,m is/are
The conversion of $ICl$ to $ICl^+$ involve(s)
Iron is extracted from its ore via the reaction
$Fe_2O_3, + 3 CO→ 2 Fe + 3CO_2$
The volume of CO (at STP) required to produce 1 kg of iron is ________liters. (round off to the nearest integer)
[Given: Atomic wt. of Fe = 56; assume STP to be 0 Β°C and 1 atm]
At constant volume, 1.0 kJ of heat is transferred to 2 moles of an ideal gas at 1 atm and 298 K. The final temperature of the ideal gas is ____K. (round off to one decimal place)
[Given: R = 8.314 J K-1 mol-1]

The heat of formation of MgO at 300 K and 1 bar pressure is -600.60 kJ mol$^{-1}$. The free energy (in kJ mol$^{-1}$) of formation of MgO at 280 K is ......... (Round off to nearest integer)

Sea water containing 1 M NaCl has to be desalinated at 300 K using a membrane permeable only to water. The minimum pressure (in bars) required on the sea-water side of the membrane is ......... (Round off to one decimal place)
In water, the enthalpy of a protein in its folded state (\(H_f\)) is lower than that in its unfolded state (\(H_{UF}\)). The entropies of the folded and unfolded states are \(S_f\) and \(S_{UF}\), respectively. The condition(s) under which this protein spontaneously folds in water at a temperature \(T\), is(are)

The graph that represents the temperature (T) – entropy (S) variation of a Carnot cycle is 


 

The CORRECT expression that corresponds to reversible and adiabatic expansion of an ideal gas is
The CORRECT expression(s) for isothermal expansion of 1 mol of an ideal gas is(are)

Consider the reaction \( \text{CO}(g) + \frac{1}{2} \text{O}_2(g) \longrightarrow \text{CO}_2(g) \).
The value of \( \Delta U \) for the reaction at 300 K is -281.8 kJ mol\(^{-1}\). The value of \( \Delta H \) at same temperature is ......... kJ mol\(^{-1}\). 
[R = 8.3 J K\(^{-1}\) mol\(^{-1}\)] 
 

The value of \( C_v \) for 1 mol of \( \text{N}_2 \) gas predicted from the principle of equipartition of energy, ignoring vibrational contribution, is .......... J K\(^{-1}\) mol\(^{-1}\) (rounded up to two decimal places).