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 enthalpy change for the reaction
would be:
1. | 2. | ||
3. | 4. |
For an isolated system with ∆U = 0, the ∆S value will be:
1. | Positive | 2. | Negative |
3. | Zero | 4. | Not possible to define |
For the reaction at 298 K,
2A + B → C
ΔH = 400 kJ mol−1 and ΔS = 0.2 kJ K−1 mol−1. The reaction will become spontaneous at:
1. | 1500 K | 2. | 2000 K |
3. | 100 K | 4. | 1900K |
The value of ∆G° for the given reaction would be:
\( 2 \mathrm{~A}(\mathrm{~g})+\mathrm{B}(\mathrm{~g}) \rightarrow 2 \mathrm{D}(\mathrm{~g})\)
(Given: ∆U° = – 10.5 kJ and ∆S° = – 44.1 J K–1)
1. | 1.6 J | 2. | –0.16 kJ |
3. | 0.16 kJ | 4. | 1.6 kJ |
The equilibrium constant for a reaction is 10. The value of
(
Entropy change in surroundings when 1.00 mol of
If for a certain reaction
1. | 70 | 2. | –33 |
3. | 33 | 4. | –70 |
1. | -92.4 J (mol)-1 | 2. | -46.2 kJ (mol)-1 |
3. | +46.2 J (mol)-1 | 4. | +92.4 kJ (mol)-1 |
The enthalpy of formation of
\(\mathrm{N_{2} O_{4 \left(g\right)} + 3 CO{\left(g\right)} \rightarrow N_{2} O_{\left(g\right)} + 3CO_{2 \left(g\right)}}\)
1. | \(- 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) | 2. | \(\) \(+ 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) |
3. | \(\) \(+ 824 . 9\) \(kJ\) \(\text{mol}^{- 1}\) | 4. | \(-\) \(345 . 4\) \(kJ\) \(\text{mol}^{- 1}\) |