The unit of entropy is -
1. J mol–1
2. JK mol–1
3. J mol–1 K–1
4. J–1 K–1 mol–1
The enthalpy and entropy change for the reaction :
Br2 (l) + Cl2 (g) 2BrCl (g)
are 30 kJ mol-1 and 105 J K-1 mol-1 respectively.
The temperature at which the reaction will be in equilibrium is :
1. | 285.7 K | 2. | 273.4 K |
3. | 450.9 K | 4. | 300.1 K |
Which of the following is not correct?
1. is zero for a reversible reaction.
2. is positive for a spontaneous reaction.
3. is negative for a spontaneous reaction.
4. is positive for a non-spontaneous reaction.
Assertion (A): | A liquid crystallizes into a solid and is accompanied by a decrease in entropy. |
Reason (R): | In crystals, molecules organize in an ordered manner. |
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. | (A) is false but (R) is true. |
Entropy decreases during:
1. Crystallization of sucrose from solution
2. Rusting of iron
3. Melting of ice
4. Vaporization of camphor
The entropy change in the fusion of one mole of a solid melting at 27C is -
(the latent heat of fusion is 2930 J mol-1)
1. 9.77 JK-1mol-1
2. 19.73 JK-1mol-1
3. 2930 JK-1mol-1
4. 108.5 JK-1mol-1
At a temperature of 300K, what is the entropy change for the reaction given below?
2H2 (g) + O2 (g) 2H2O(l)
Standard entropies of H2 (g), O2(g) and H2O(l) are 126.6, 201.20 and 68.0 JK-1mol-1 respectively.
1. -318.4 JK-1mol-1
2. 318.4 JK-1mol-1
3. 31.84 JK-1mol-1
4. None of the above
Match the following process with entropy change
Reaction | Entropy change |
A. A liquid vaporizes | 1. |
B. Reaction is non-spontaneous at all temperatures and is positive | 2. |
C. Reversible expansion of an ideal gas | 3. |
Codes
A | B | C | |
1. | 2 | 3 | 1 |
2. | 1 | 2 | 3 |
3. | 1 | 3 | 2 |
4. | 3 | 2 | 1 |
For the reaction, , the value of ∆H and ∆S are respectively -
1.
2.
3.
4.
Match the following parameters with a description for spontaneity.
\(\Delta\) (Parameters) \(\Delta r\ H^⊝\) \(\Delta r\ S^⊝\)\(\Delta r\ G^⊝\) | Description |
A. + - + | 1. Non-spontaneous at high temperature |
B. - - + at high T | 2. Spontaneous at all temperatures |
C. - + - | 3. Non-spontaneous at all temperatures |
Codes
A | B | C | |
1. | 3 | 1 | 2 |
2. | 1 | 2 | 3 |
3. | 1 | 3 | 2 |
4. | 3 | 2 | 1 |