At 1 atm pressure, 
\(\mathrm{\Delta S = 75 \ JK^{-1} mol^{-1} \ and \ \Delta H = 30 \ kJ mol^{-1} }\).
The temperature at which the reaction attains equilibrium is:
1. 400 K  2. 330 K 
3. 200 K  4. 110 K 

Subtopic:  Spontaneity & Entropy |
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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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At which of the following conditions does a reaction with positive \(\Delta \mathrm{H} \) becomes spontaneous?
1. \(\Delta S=+ve \) , low temperature
2. \(\Delta S=+ve, \) high temperature
3. \(\Delta S=-ve,\) at all temperature
4. \(\Delta S=- \text {ve}\), at low temperature
Subtopic:  Spontaneity & Entropy |
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Given below are two statements:
Assertion (A): Variables like P, V, and T are called state functions.
Reason (R):

Their values depend solely on the system's state, and not on how it is reached.

 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Thermodynamics' Properties and process |
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The reaction, among the following, that has ∆S° > 0 is:
1. S8(l) → S8(s, monoclinic)
2. H2(g) + O2(g) → H2O2(aq)
3. H2(g) + 2 Ag+(aq) → 2 H+(aq) + 2 Ag(s)
4. PCl5(g) → PCl3(g) + Cl2(g)
Subtopic:  Spontaneity & Entropy |
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A sample of 54.0g of methanol is heated from 25.0°C to 35.0°C. The amount of heat required is: (Given: The specific heat capacity of methanol is 2.48 J g–1 K–1)
1. 0.00459 J 2. 0.0747 J
3. 1340 J 4. 4690 J
Subtopic:  Enthalpy & Internal energy |
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Match Column I (Reactions) with Column II (Enthalpy) and mark the appropriate choice:
 
Column I (Reactions) Column II (Enthalpy)
(A) \(\small{CH_{4(g)} + 2O_{2(g)} \rightarrow CO_{2(g)} + 2H_2O}\) (i) \(\Delta _{sol}H^o\)
(B) \( H_{2(g)} \rightarrow 2H_{(g)}\) (ii) \(\Delta _{lattice}H^o\)
(C) \(NaCl_{(s)} \rightarrow Na^+_{(g)} + Cl^-_{(g)} \) (iii) \(\Delta _{c}H^o\)
(D) \(NaCl_{(s)} \rightarrow Na^+_{(aq)} + Cl^-_{(aq)} \) (iv) \(\Delta _{bond}H^o\)

1. (A) →(iv), (B)→(iii), (C) →(i), (D)→ (ii)
2. (A) →(ii), (B)→(i), (C) →(iv), (D)→ (iii)
3. (A) →(i), (B)→(ii), (C) →(iii), (D)→ (iv)
4. (A) →(iii), (B)→(iv), (C) →(ii), (D)→ (i)
Subtopic:  Thermochemistry |
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What is the enthalpy change (ΔH) for the reaction represented by the equation, \(\mathrm{OF_2 + H_2O \rightarrow O_2+2HF?}\)
[Given the bond energies of \(\mathrm{O-F, O-H, H-F}\) \(\mathrm {and~O=O}\) as 44, 111, 135, and 119 kcal mol–1, respectively]
 
1. –222 kcal  2. –88 kcal 
3. –111 kcal 4. –79 kcal 
Subtopic:  Thermochemistry |
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Match Column-I with Column-II and mark the appropriate choice:
Column-I Column-II
(A) State Function (i) At constant pressure
(B) \(\Delta H = q\) (ii) Specific heat
(C) \(\Delta U = q\) (iii) Entropy
(D) Intensive property (iv) At constant volume 

1. (A) →(iii), (B)→(i), (C) →(iv), (D)→ (ii)
2. (A) →(ii), (B)→(iv), (C) →(i), (D)→ (iii)
3. (A) →(ii), (B)→(iv), (C) →(iii), (D)→ (i)
4. (A) →(iii), (B)→(ii), (C) →(i), (D)→ (iv)
Subtopic:  Enthalpy & Internal energy | Classification of System, Extensive & Intensive Properties |
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The temperature at which the given reaction is in equilibrium is:
\(\mathrm{X_{(g)} +3Y_{(g)} \rightleftharpoons 2Z_{(g)} ; \Delta H= -40~ kJ ~mol^{-1}}~\)
(The standard entropies of X, Y, and Z are 60, 40, and 50 J K–1 mol–1, respectively.) 

1. 273 K 
2. 600 K 
3. 500 K 
4. 400 K 
Subtopic:  2nd & 3rd Law of Thermodynamics |
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