The heat of combustion of carbon to CO2 is –393.5 KJ/mol. The heat released upon the formation of 35.2 g of CO2 from carbon and oxygen gas is:
1. –315 KJ
2. +315 KJ
3. –630 KJ
4. +630 KJ
The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0 oC is:
1. 10.52 cal/(mol K)
2. 21.04 cal/(mol K)
3. 5.260 cal/(mol K)
4. 0.526 cal/(mol K)
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 |
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
The enthalpy of combustion of H2, cyclohexene (C6H10) and cyclohexane (C6H12) are -241, -3800 and -3920 kJ per mol respectively. Heat of hydrogenation of cyclohexene is:
1. -121 kJ per mol
2. +121 kJ per mol
3. +242 kJ per mol
4. -242 kJ per mol