The maximum work done in expanding 16 g of oxygen at 300 K and occupying a volume of 5 dm3 isothermally until the volume becomes 25 dm3 is:
1. -2.01 x 103 J
2. 2.81 x 103 J
3. 2.01 x 10-3 J
4. -2.01 x 10-6 J
1 mole of an ideal gas at 25 is subjected to expand reversibly ten times of its initial volume.
The change in entropy of expansion is:
1. 19.15 JK–1mol–1
2. 16.15 JK–1mol–1
3. 22.15 JK–1mol–1
4. None of the above
For the process
H2O(l) H2O(g)
at T=100C and 1 atmosphere pressure, the correct choice is:
1.
2.
3.
4.
During an adiabatic process:
1. pressure is maintained constant
2. gas is isothermally expanded
3. there is perfect heat insulation
4. the system changes heat with surroundings
Heat of combustion for C(s), H2(g) and CH4(g) are -94, -68 and -213 kcal/mol. Then, for
C(s) + 2H2(g) CH4(g) is
1. -17 kcal/mol
2. -111 kcal/mol
3. -170 kcal/mol
4. -85 kcal/mol
What is the resulting change in the internal energy of the system when 50 calories are added to
the system and the system does work of 30 calories on the surroundings?
1. 20 cal
2. 50 cal
3. 40 cal
4. 30 cal
For the process:
H2O(l)[1 bar, 373 K] H2O(g)[1 bar, 373 K] the correct set of thermodynamic parameters are:
1.
2.
3.
4.
The internal energy change when a system goes from state A to B is 40 kJ/mol. If the system goes from A to B by a reversible path and returns to state A by an irreversible path. What would be the change in internal energy?
1. 40 kJ
2. >40 kJ
3. <40 kJ
4. Zero
Change in entropy is negative for:
1. Bromine (l)Bromine(g)
2. C(s) + H2O(g) CO(g) + H2(g)
3. N2(g,10 atm)N2(g,1 atm)
4. Fe ( 1mol, 400 K) Fe( 1mol, 300 K)
The mathematical form of the first law of thermodynamics when heat (q) is supplied and W is work done by the system (-ve) is:
1. U=q+W
2. U=q-W
3. U=-q+W
4. U= -q-W