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 correct statement for a reversible process in a state of equilibrium is:
1. G = – 2.30RT log K
2. G = 2.30RT log K
3. Go = – 2.30RT log K
4. Go = 2.30RT log K
For the reaction:
\(\mathrm{X}_2 \mathrm{O}_4(l) \rightarrow 2 \mathrm{XO}_2(g)\)
with the given values \(\Delta U = 2.1 \, \text{kcal}\) and \(\Delta S = 20 \, \text{cal K}^{-1}\) at \(300 \, \text{K}\), what is the value of \(\Delta G\)?
1. 2.7 kcal
2. –2.7 kcal
3. 9.3 kcal
4. –9.3 kcal
(i) | C(graphite) + O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = x kJ mol–1 |
(ii) | Cgraphite + 1/2 O2(g) \(\rightarrow\) CO(g); \(\Delta_{r}\)H° = y kJ mol–1 |
(iii) | CO(g) + 1/2 O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = z kJ mol–1 |
1. | z = x + y | 2. | x = y + z |
3. | y = 2z – x | 4. | x = y – z |
In which of the following reactions, the standard reaction entropy change
is positive, and standard Gibb's energy change
decreases sharply with increasing temperature?
1. | C(graphite) + \(\frac{1}{2}\)O2(g) → CO(g) |
2. | CO(g) + \(\frac{1}{2}\)O2(g) → CO2(g) |
3. | Mg(s) + \(\frac{1}{2}\)O2(g) → MgO(s) |
4. | \(\frac{1}{2}\)C(graphite) + \(\frac{1}{2}\)O2(g) → \(\frac{1}{2}\)CO2(g) |
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)
The standard enthalpy of vaporization for water at 100 oC is 40.66 kJ mol-1.
The internal energy of vaporization of water at 100 oC (in kJ mol-1) is:
(Assume water vapour behaves like an ideal gas.)
1. +37.56
2. -43.76
3. +43.76
4. +40.66
Equal volumes of two monoatomic gases, A and B, at same temperature and pressure are mixed. The ratio of specific heats (Cp/Cv) of the mixture will be:
1. 1.50
2. 3.3
3. 1.67
4. 0.83