A container of gas is at a pressure of 1.3 x 10^5 pa and a volume of 6.0 m^3. how much work is done by the gas if it expands at a constant pressure to twice its initial volume
For the answer to the question above, since the process is carried out at constant pressure,
work = P (V1-V2)
= 1.3 E5 (6-12) = -7.8 E5 N.m (in this case the work is made by the system, so it is negative if work made on the system then it should be positive)
Answer: The work done for the given process is -778 kJ
Explanation:
To calculate the amount of work done for an isothermal process is given by the equation:
\(W=-P\Delta V=-P(V_2-V_1)\)
W = amount of work done = ?
P = pressure of the container = \(1.3\times 10^5Pa=1.28atm\) (Conversion factor: \(1atm=1.013\times 10^5Pa\) )
\(V_1\) = initial volume = \(6.0m^3=6000L\) (Conversion factor: \(1m^3=1000L\) )
\(V_2\) = final volume = \((2\times V_1)=(2\times 6000)=12000L\)
Putting values in above equation, we get:
\(W=-1.28atm\times (12000-6000)L=-7680L.atm\)
To convert this into joules, we use the conversion factor:
\(1L.atm=101.33J\)
1 kJ = 1000 J
So, \(-7680L.atm=-35\times 101.3=-777984J=-778kJ\)
The negative sign indicates the system is doing work.
Hence, the work done for the given process is -778 kJ