2 mole of an ideal gas at 27ºC temp. is expanded reversibly from 2 lit. to 20 lit. Find entropy change (R = 2 cal/mol K):
| 1. | 92.1 | 2. | 0 |
| 3. | 4 | 4. | 9.2 |
Given that the standard heats of combustion (ΔH°) of C(s), H₂(g), and CH₄(g)
are −94 kcal/mol, −68 kcal/mol, and −213 kcal/mol, respectively.
What is the standard enthalpy change (ΔH°) for the reaction:
C(s) + 2H₂(g) → CH₄(g)?
| 1. | – 17 Kcal | 2. | – 111 Kcal |
| 3. | – 170 Kcal | 4. | – 85 Kcal |
When 1 mol gas is heated at constant volume, the temperature is raised from 298 to 308 K. Heat supplied to the gas is 500 J. The correct statement among the following is:
1. q = w = 500 J, ∆U = 0
2. q = ∆U = 500 J, w = 0
3. q =0, w = 500 J, ∆U = 0
4. ∆U = 0, q = w = – 500 J
The densities of graphite and diamond at 298 K are 2.25 and 3.31 g cm–3, respectively. If the standard free energy difference (∆Gº) is equal to 1895 J mol–1, the pressure at which graphite will be transformed into diamond at 298 K is:
1. 11.08
2.
3.
4. 11.08
What is the entropy change (in JK–1 mol–1) when one mole of ice is converted into water at 0 ºC?
(The enthalpy change for the conversion of ice to liquid water is 6.0 KJ mol–1 at 0 ºC)
| 1. | 20.13 | 2. | 2.013 |
| 3. | 2.198 | 4. | 21.98 |
The formation of a solution from two components can be considered as:
| (i) | Pure solvent → separated solvent molecules, ∆H1 |
| (ii) | Pure solute → separated solute molecules, ∆H2 |
| (iii) | Separated solvent and solute molecules → solution, ∆H3 |
The solution so formed will be ideal if:
1. ∆HSoln = ∆H1 + ∆H2 + ∆H3
2. ∆HSoln = ∆H1 + ∆H2 – ∆H3
3. ∆HSoln = ∆H1 – ∆H2 – ∆H3
4. ∆HSoln = ∆H3 – ∆H1 – ∆H2
The molar heat capacity of water at constant pressure, C, is 75 JK–1 mol–1. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand, the increase in temperature of the water is:
| 1. | 1.2 K | 2. | 2.4 K |
| 3. | 4.8 K | 4. | 6.6 K |
1. Less than NO2(g)
2. More than NO2(g)
3. Equal to NO2(g)
4. Insufficient data
What is the entropy change of the surroundings when 1.00 mol of liquid water (H₂O(l))
is formed under standard conditions?
[Given: ∆fHθ = –286 kJ mol–1 ]
1. 952. 5 J mol-1
2.
3.
4.
For the graph given below, it can be concluded that work done during the process shown will be:
| 1. | Zero | 2. | Negative |
| 3. | Positive | 4. | Cannot be determined |