Advertisements
Advertisements
प्रश्न
3 mole of a gas at temperature 400 K expands isothermally from an initial volume of 4 litres to a final volume of 8 litres. Find the work done by the gas. (R = 8.31 J mol-1 K-1)
Advertisements
उत्तर
Given:
n = 3 mol, T = 400 K, Vi = 4 L, Vf = 8 L, R = 8.31 J mol-1 K-1
To find: Work done by gas (W)
Formula: `"W"_"isothermal"` = nRT In`"V"_"f"/"V"_"i"`
Calculation:
From formula (i),
W = 3 × 8.31 × 400 × In`(8/4)`
Now, ln x = 2.303 × log (x)
∴ In`(8/4)` = ln (2) = 2.303 log (2)
∴ W = 1200 × 8.31 × 2.303 × 0.3010
= antilog{log(1200) + log(8.31) + log (2.303) + log(0.3010)}
= antilog{3.0792 + 0.9196 + 0.3623 + (`overline1`.4786 )}
= antilog{3.8397}
= 6.913 × 103 J
= 6.913 kJ
Work done by the gas is 6.913 kJ.
APPEARS IN
संबंधित प्रश्न
Draw a p-V diagram of the reversible process.
Draw a p-V diagram of the irreversible process.
Draw a p-V diagram showing positive work with varying pressure.
Draw a p-V diagram showing negative work with varying pressure.
Differentiate between the reversible and irreversible processes.
Explain the cyclic process.
Write a note on free expansion.
Explain the thermodynamics of the isochoric process.
When a cycle tyre suddenly bursts, the air inside the tyre expands. This process is ____________.
Apply first law for an adiabatic process.
Apply first law for an isobaric process.
Give an equation state for an isochoric process.
Draw the PV diagram for the isobaric process.
Can the given heat energy be completely converted to work in a cyclic process? If not, when can the heat can completely converted to work?
Explain in detail the isothermal process.
Derive the work done in an isothermal process.
Explain the isobaric process and derive the work done in this process.
Draw the TP diagram (P-x axis, T-y axis), VT(T-x axis, V-y axis) diagram for
- Isochoric process
- Isothermal process
- Isobaric process
Consider the following cyclic process consist of isotherm, isochoric and isobar which is given in the figure.

Draw the same cyclic process qualitatively in the V-T diagram where T is taken along the x-direction and V is taken along the y-direction. Analyze the nature of heat exchange in each process.
An ideal gas is taken in a cyclic process as shown in the figure. Calculate
- work done by the gas
- work done on the gas
- Net work done in the process

For a given ideal gas 6 × 105 J heat energy is supplied and the volume of gas is increased from 4 m3 to 6 m3 at atmospheric pressure. Calculate
- the work done by the gas
- change in internal energy of the gas
- graph this process in PV and TV diagram
A monoatomic gas of pressure p having volume V expands isothermally to a volume 2V and then adiabatically to a volume 16V. The final pressure of the gas is ____________.
`("ratio of specific heats" = 5/3)`
For an isothermal expansion of a perfect gas, the value of `(Delta "P")/"P"` is equal to ____________.
We consider a thermodynamic system. If `Delta"U"` represents the increase in its internal energy and W the work done by the system, which of the following statements is true?
The work done on the system in changing the state of a gas adiabatically from equilibrium state A to equilibrium state B is 22.4 J. If the gas is taken from state A to B through another process in which the net heat absorbed by the system is 15.5 cal, then the net work done by the system in the latter case is ______.
( l cal = 4.2 J)
Which of the following processes is reversible?
In a certain thermodynamical process, the pressure of a gas depends on its volume as kV3. The work done when the temperature changes from 100°C to 300°C will be ______ nR, where n denotes number of moles of a gas.
An ideal gas is taken through a cyclic process ABCDA as shown in figure. The net work done by the gas during the cycle is ______.

Explain how can a gas be expanded at constant temperature.
