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 |
Consider the following diagram for a reaction .
The nature of the reaction is-
1. Exothermic
2. Endothermic
3. Reaction at equilibrium
4. None of the above
Which of the following statements is correct for an irreversible isothermal expansion of an ideal gas?
1.
2.
3.
4.
At standard conditions, if the change in the enthalpy for the following reaction is –109 kJ mol–1
H2(g)+Br2(g)2HBr(g) and the bond energy of H2 and Br2 is 435 kJ mol–1 and 192 kJ mol–1 respectively, what is the bond energy (in kJ mol–1) of HBr?
| 1. | 368 | 2. | 736 |
| 3. | 518 | 4. | 259 |
If for a certain reaction is 30 kJ mol–1 at 450 K, the value of (in JK–1 mol–1) for which the same reaction will be spontaneous at the same temperature is:
| 1. | 70 | 2. | –33 |
| 3. | 33 | 4. | –70 |
The standard enthalpy of the formation of CH3OH(l) from the following data is:
| \(\small{\mathrm{CH}_3 \mathrm{OH}_{(l)}+\frac{3}{2} \mathrm{O}_2(\mathrm{g}) \rightarrow \mathrm{CO}_2(\mathrm{g})+2 \mathrm{H}_2 \mathrm{O}_{(l)} \text {; }}\) \( \Delta_{\mathrm{r}} \mathrm{H}^{\circ}=-726 \mathrm{~kJ} \mathrm{~mol}{ }^{-1}\) |
| \(\small{\mathrm{C}(\mathrm{s})+\mathrm{O}_2(\mathrm{g}) \rightarrow \mathrm{CO}_2(\mathrm{g}) \text {; } }\) \(\Delta_{\mathrm{c}} \mathrm{H}^{\circ}=-393 \mathrm{~kJ} \mathrm{~mol}{ }^{-1}\) |
| \(\small{\mathrm{H}_{2(\mathrm{g})}+\frac{1}{2} \mathrm{O}_{2(\mathrm{g})} \rightarrow \mathrm{H}_2 \mathrm{O}_{(l)} \text {; } } \) \(\Delta_{\mathrm{f}} \mathrm{H}^{\circ}=-286 \mathrm{~kJ} \mathrm{~mol}^{-1}\) |
| 1. | −239 kJ mol−1 | 2. | +239 kJ mol−1 |
| 3. | −47 kJ mol−1 | 4. | +47 kJ mol−1 |
The amount of heat needed to raise the temperature of 60.0 g of aluminium from 35°C to 55°C would be:
(Molar heat capacity of Al is \(24\) \(J\) \(\text{mol}^{- 1}\) \(K^{- 1}\))
| 1. | \(1 . 07\) \(J\) | 2. | \(1 . 07\) \(kJ\) |
| 3. | \(106 . 7\) \(kJ\) | 4. | \(100 . 7\) \(kJ\) |
The enthalpy of formation of all elements in their standard state is-
| 1. | Unity | 2. | Zero |
| 3. | Less than zero | 4. | Different for each element |
Which among the following statements about open, closed, and isolated systems is correct?
| 1. | The presence of reacting species in a covered beaker represents an open system. |
| 2. | In a closed system, there is an exchange of both energy and matter between the system and its surroundings. |
| 3. | A system containing reactants in a closed vessel made of copper is an example of a closed system. |
| 4. | A system containing reactants in a thermos flask or any other closed, insulated vessel is an example of a closed system. |
Match the following parameters with a description for spontaneity.
| \(\Delta r\ H^⊝\) | \(\Delta r\ S^⊝\) | \(\Delta r\ G^⊝\) | Description | ||
| A. | + | – | + | 1. | Non-spontaneous at high temperature |
| B. | – | – | + | 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 |