From the following bond energies:
H—H bond energy: 431.37 kJ mol-1
C=C bond energy: 606.10 kJ mol-1
C—C bond energy: 336.49 kJ mol-1
C—H bond energy: 410.50 kJ mol-1
Enthalpy for the reaction,
will be:
1. | 1523.6 kJ mol-1 | 2. | -243.6 kJ mol-1 |
3. | -120.0 kJ mol-1 | 4. | 553.0 kJ mol-1 |
The values of ΔH and ΔS for the given reaction are 170 kJ and 170 JK-1, respectively.
C(graphite) + CO2(g)→2CO(g)
This reaction will be spontaneous at:
1. 710 K
2. 910 K
3. 1110 K
4. 510 K
1. ΔH = 0 and ΔS < 0
2. ΔH > 0 and ΔS > 0
3. ΔH < 0 and ΔS < 0
4. ΔH > 0 and ΔS < 0
1. 1.968 V
2. 2.0968 V
3. 1.0968 V
4. 0.0968 V
1. 93 kJ mol-1
2. - 245 kJ mol-1
3. -93 kJ mol-1
4. 245 kJ mol-1
Consider the following reactions:
(i) | H+(aq) + OH-(aq) → H2O(l) ΔH = -x1 kJmol-1 |
(ii) | H2(g) + 1/2O2(g) → H2O(l) ΔH = -x2 kJmol-1 |
(iii) | CO2(g) + H2(g) → CO (g) + H2O(l) ΔH = -x3 kJmol-1 |
(iv) | C2H2(g) + 5/2O2(g) → 2CO2 + H2O(l) ΔH = -x4 kJmol-1 |
Enthalpy of formation of H2O(l) is :
1.
2.
3.
4.
The bond energy of H—H and Cl-Cl is 430 kJ mol-1 and 240 kJ mol-1 respectively
and ΔHf for HCl is -90 kJ mol-1. The bond enthalpy of HCl is:
1. 290
2. 380
3. 425
4. 245
1. | Carbon and hydrogen act as suitable reducing agents for metal sulphides |
2. | The \(\Delta_f G^0\) of the sulphide is greater than those for \(C S_2\) and \(\mathrm{H}_2 \mathrm{~S}\) |
3. | The \(\Delta_f G^0\) is negative for roasting of sulphur ore to oxide. |
4. | Roasting of the sulphide to the oxide is thermodynamically feasible |
Identify the correct statement for change of Gibbs energy for a system (ΔGsystem) at constant temperature and pressure:
1. | If \(\begin{equation} \Delta G_{\text {system }} \end{equation}\) > 0 , the process is spontaneous |
2. | If \(\begin{equation} \Delta G_{\text {system }} \end{equation}\) = 0 , the system has attained equilibrium |
3. | If \(\begin{equation}
\Delta G_{\text {system }}
\end{equation}\) = 0 , the system is still moving in a particular direction. |
4. | If \(\begin{equation} \Delta G_{\text {system }} \end{equation}\)< 0 , the process is not spontaneous |