How Do You Calculate Work Done by Gas in Thermodynamics?

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To calculate the work done by gas during expansion at constant pressure, the formula W = P(Vf - Vi) is used. The pressure of 95 atmospheres was correctly converted to Pascals, resulting in 9,623,500 Pa. However, the volume conversion was incorrect; 5 L and 10 L should be converted to cubic meters as 0.005 m^3 and 0.010 m^3, respectively. The correct calculation of work done would yield a different result than the initially calculated 4,811,750 Joules. Accurate unit conversion is crucial for obtaining the correct answer in thermodynamics problems.
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Thermodynamics problem: help needed!

Gas in a container expands at a constant pressure of 95 atmospheres. Find the work done by the gas if the initial volume is 5 L and the final volume is 10 L. Answer in units of Joules.

I thought this problem was straight-forward, but I missed it.

I converted 95 atmospheres into Pascals.

95 X 1.013e5 PA = 9623500

I then converted L into meters ^3.

Vi = 0.5 m^3
Vf = 1 m^3

With the units converted, I used the equation W = P(Vf - Vi) and got the answer 4811750 Joules. The answer is incorrect, or so I believe.

Where did I go wrong?
 
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Enoch said:
Gas in a container expands at a constant pressure of 95 atmospheres. Find the work done by the gas if the initial volume is 5 L and the final volume is 10 L. Answer in units of Joules.

I thought this problem was straight-forward, but I missed it.

I converted 95 atmospheres into Pascals.

95 X 1.013e5 PA = 9623500

I then converted L into meters ^3.

Vi = 0.5 m^3
Vf = 1 m^3

With the units converted, I used the equation W = P(Vf - Vi) and got the answer 4811750 Joules. The answer is incorrect, or so I believe.

Where did I go wrong?

There's no problem with the conversion of the pressure's units to SI,but remember that
1m^3=1000L
 
dextercioby said:
There's no problem with the conversion of the pressure's units to SI,but remember that
1m^3=1000L

Thanks alot!
 
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