What is a necessary condition for an adiabatic process to occur?

1. ∆T = 0

2. ∆P = 0

3. q = 0

4. w = 0

Subtopic:  Thermodynamics' Properties and process |
 90%
Level 1: 80%+
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The enthalpy of formation of all elements in their standard state is-

1. Unity 2. Zero
3. Less than zero 4. Different for each element
Subtopic:  Thermodynamics' Properties and process |
 82%
Level 1: 80%+
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U° for combustion of methane is –x kJ mol–1.

The value of H° for the same reaction would be:

1. = U°
2. > U°
3. < U°
4. =0

Subtopic:  Enthalpy & Internal energy |
 66%
Level 2: 60%+
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The enthalpy of combustion of methane, graphite, and dihydrogen at 298 K are, –890.3 kJ mol1 , –393.5 kJ mol-1, and –285.8 kJ mol–1 respectively. The enthalpy of formation of CH4(g) is:

1. –74.8 kJ mol–1 2. –52.27 kJ mol–1
3. +74.8 kJ mol–1 4. +52.26 kJ mol–1
Subtopic:  Thermochemistry |
 67%
Level 2: 60%+
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 For the reaction A + B → C + D + q (kJ/mol), entropy change is positive. The reaction will be :

1. Possible only at high temperature

2. Possible only at low temperature

3. Not possible at any temperature

4. Possible at any temperature

Subtopic:  Spontaneity & Entropy |
 59%
Level 3: 35%-60%
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701 J of heat is absorbed by a system and 394 J of work is done by the system. The change in internal energy for the process is:

1. 307 J 2. -307 J
3. 1095 J 4. -701 J
Subtopic:  First Law of Thermodynamics |
 83%
Level 1: 80%+
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The reaction of cyanamide, NH2CN (s) with dioxygen, was carried out in a bomb calorimeter, and ∆U was found to be -742.7 kJ mol-1 at 298 K:
\(\small{\mathrm{NH}_2 \mathrm{CN}(\mathrm{s})+\frac{3}{2} \mathrm{O}_2(\mathrm{g}) \rightarrow \mathrm{N}_2(\mathrm{g})+\mathrm{CO}_2(\mathrm{g})+\mathrm{H}_2 \mathrm{O}(\mathrm{l})}\)

The enthalpy change for the reaction at 298 K would be:

1. -741.3 kJ mol-1
2. + 753.9 kJ mol-1
3. + 772. 7 kJ mol-1
4. -845. 1 kJ mol-1

Subtopic:  Enthalpy & Internal energy |
 76%
Level 2: 60%+
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The amount of heat needed to raise the temperature of 60.0 g of aluminium from 35°C to 55°C would be:

(Molar heat capacity of Al is \(24\) \(J\) \(\text{mol}^{- 1}\) \(K^{- 1}\))

1. \(1 . 07\) \(J\) 2. \(1 . 07\) \(kJ\)
3. \(106 . 7\) \(kJ\) 4. \(100 . 7\) \(kJ\)
Subtopic:  Thermodynamics' Properties and process |
 68%
Level 2: 60%+
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The enthalpy of combustion of carbon to CO2 is –393.5 kJ mol-1. The amount of heat released upon formation of 35.2g of CO2 from carbon and dioxygen gas would be:

1. –393.5 kJ mol–1 2. –314.8 kJ mol–1
3. +314.8 kJ mol–1 4. –320.5 kJ mol–1
Subtopic:  Thermochemistry |
 76%
Level 2: 60%+
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The enthalpy of formation of COg, CO2g, N2Og , and N2O4g are –110 kJ mol-1, – 393 kJ mol-1, 81 kJ mol-1, and 9.7 kJ \(\text{mol}^{- 1}\) respectively. The value of \(\left(\Delta\right)_{r} H\) for the following reaction would be:

\(\mathrm{N_{2} O_{4 \left(g\right)} + 3 CO{\left(g\right)} \rightarrow N_{2} O_{\left(g\right)} + 3CO_{2 \left(g\right)}}\)

1. \(- 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\) 2. \(\) \(+ 777 . 7\) \(kJ\) \(\text{mol}^{- 1}\)
3. \(\) \(+ 824 . 9\) \(kJ\) \(\text{mol}^{- 1}\) 4. \(-\) \(345 . 4\) \(kJ\) \(\text{mol}^{- 1}\)
Subtopic:  Thermochemistry |
 77%
Level 2: 60%+
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