The thermodynamic stability of NO(g) based on the above data is:
1. Less than NO2(g)
2. More than NO2(g)
3. Equal to NO2(g)
4. Insufficient data
The entropy change in the surroundings when 1.00 mol of H2O(l) is formed under standard conditions is:
∆fHθ = –286 kJ mol–1
1. 952.5 J mol-1
2.
3.
4.
The equilibrium constant for a reaction is 10. The value of will be:
( )
For the reaction 2A(g) + B(g) → 2D(g) ; ∆U° = – 10.5 kJ and ∆S° = – 44.1 J K–1, the value of ∆G° for the given reaction would be-
1. | 1.6 J | 2. | –0.16 kJ |
3. | 0.16 kJ | 4. | 1.6 kJ |
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 |
For an isolated system with ∆U = 0, the ∆S value will be:
1. | Positive | 2. | Negative |
3. | Zero | 4. | Not possible to define |
The enthalpy change for the reaction
would be:
1. | 2. | ||
3. | 4. |
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 |
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
The value of \(\left(\Delta\right)_{r} H\) for the reaction would be:
\(\mathrm{N_{2} O_{4 \left(g\right)} + 3 \left(CO\right)_{\left(g\right)} \rightarrow N_{2} O_{\left(g\right)} + 3 \left(CO\right)_{2 \left(g\right)}}\)
1. | \(- 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) | 2. | \(\) \(+ 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) |
3. | \(\) \(+ 824 . 9\) \(kJ\) \(\text{mol}^{- 1}\) | 4. | \(-\) \(345 . 4\) \(kJ\) \(\text{mol}^{- 1}\) |