Match the entries in Column-I with those given in Column-II:
Column-I Column-II
(A) Reversible process (p) \(\Delta G = -nFE\)
(B) Gibbs free energy (q) Infinite steps
(C) Standard enthalpy of reaction, \(\Delta_r H^{\ominus}\) (r) \(\sum\)bond enthalpies (reactants) – 
\(\sum\)bond enthalpies (products) 
(D) Enthalpy of bond formation, \(\Delta_f H_{\text {bond }}^{\ominus}\) (s) \(\sum \Delta_f H^{\ominus}\)(bonds of
products) 

\(\sum \Delta_f H^{\ominus}\)
(bonds
of reactants)
1. A-q, B-p, C-r, D-s
2. A-p, B-q, C-r, D-s
3. A-s, B-q, C-r, D-p
4. A-q, B-s, C-r, D-q
Subtopic:  Gibbs Energy Change | Thermochemistry |
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Identify correct match using Column I & Column II
Column I Column II
(i) Spontaneous process (a) Isothermal and isobaric process
(ii) \(\Delta H^\circ\) (b) \(\Delta H<0 \)
(iii) \(\Delta T=0, \Delta P=0 \) (c) \(\Delta G<0 \)
(iv) Exothermic process (d) (Bond energy of reactant) - (Bond energy of product)
 
I II III IV
1. c d a b
2. b a c d
3. d b c d
4. a d b c
Subtopic:  First Law of Thermodynamics | Spontaneity & Entropy | Gibbs Energy Change |
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JEE
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Tin is obtained from cassiterite by reduction with coke. What is the minimum temperature (in K) at which the reduction of cassiterite by coke would take place? 
[Note: Assume that the enthalpies and the entropies are temperature-independent]
\(\text{Given:}~\text{At } 298 \mathrm{~K} ;\)
\(\Delta H^0\left(\mathrm{SnO}_2(s)\right)=-581.0 \mathrm{~kJ} \mathrm{~mol}^{-1}, \\\Delta_f H^0\left(\mathrm{CO}_2(g)\right)=-394.0 \mathrm{~kJ} \mathrm{~mol}^{-1}, \)
\(S^0\left(\mathrm{SnO}_2(s)\right)=56.0 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}, \\S^0(\mathrm{Sn}(s))=52.0 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\)
\( S^0(\mathrm{C}(s))=6.0 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}, \\S^0\left(\mathrm{CO}_2(g)\right)=210.0 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\)

Choose the correct option:
1. 735 K
2. 303 K
3. 935 K
4. 456 K
Subtopic:  Spontaneity & Entropy | Gibbs Energy Change |
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Hydrolysis of sucrose is given by the following reaction

Sucrose + H2 Glucose + Fructose

If the equilibrium constant (Kc) is 2×1013 at 300 K, the value of rG0 at the same temperature will be:

1. 8.314 J mol-1 K-1×300 K×ln (2×1013)

2. 8.314 J mol-1 K-1×300 K×ln (3×1013)

3. -8.314 J mol-1 K-1×300 K×ln (4×1013)

4. -8.314 J mol-1 K-1×300 K×ln (2×1013)

Subtopic:  Gibbs Energy Change |
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NEET - 2020
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The free energy change due to a reaction is zero when :
 
1. The reactants are initially mixed 
2.  A catalyst is added 
3.  The system is at an equilibrium 
4.  The reactants are completely consumed 
Subtopic:  Gibbs Energy Change |
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Which of the following is the maximum energy available for useful work from a spontaneous reaction?
1. Gibbs free energy 2. Lattice energy
3. Kinetic energy 4. Ionization energy
Subtopic:  Gibbs Energy Change |
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The standard enthalpy and entropy changes of decomposition of N2O4 to NO2 are 55.0 kJmol–1 and 175.0 JK–1 mol–1 respectively. The standard free energy change for this reaction at 25°C in J mol–1 is:
1. 2750 2. 2850
3. 2875 4. 2900
Subtopic:  Spontaneity & Entropy | Gibbs Energy Change |
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Given the following reaction:
\(\mathrm{Ag}_2 \mathrm{O}(s) \rightarrow 2 \mathrm{Ag}(s)+\frac{1}{2} \mathrm{O}_2(g)\)
The values of \(\Delta H\) and \(\Delta S\) are 30.56 kJ/mol and 66.00 J/Kmol, respectively.
The temperature at which the free energy change (\(\Delta G\)) for the reaction will be zero is:

1. 563 K
2. 463 K
3. 403 K
4. 544 K
Subtopic:  Gibbs Energy Change |
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The correct thermodynamic conditions for a spontaneous reaction at all temperatures is:
1. H > 0 and S< 0
2. H < 0 and S> 0
3. H < 0 and S< 0
4. H > 0 and S = 0
Subtopic:  Gibbs Energy Change |
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NEET - 2016
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The enthalpy and entropy change for a chemical reaction are

–2.5 × 103 cal and 7.4 cal deg–1 respectively.  Predict the reaction at 298 K is

1. Spontaneous

2. Reversible

3. Irreversible

4. Non-spontaneous

Subtopic:  Gibbs Energy Change |
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