Why 1 liter * atm = 101.33 joules ?

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The discussion centers on understanding why 1 liter * atm equals 101.33 joules. Participants clarify that this relationship arises from the conversion of pressure and volume units into energy units. The gas constant values, 8.31447 J/mol K and 0.08206 L atm/mol K, are mentioned as part of the conversion process. Additionally, a direct approach using SI units for pressure and volume demonstrates that 1 atm multiplied by 1 liter results in 101 joules. The conversation emphasizes the underlying physics of work done by pressure on volume.
Tahira Firdous
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Hi ! I have been searching but i am not able to find out that is there any reason behind , why 1 liter * atm = 101.33 joules ?
 
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Are you asking why it comes out equal to 101.33 Joules, or why a pressure (atm) time a volume (liter) gives an energy (joules)?
 
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Nugatory said:
Are you asking why it comes out equal to 101.33 Joules, or why a pressure (atm) time a volume (liter) gives an energy (joules)?
I am asking that why it is equal to 101.33 joules any logical reason or just a constant ?
 
Daniel Hendriks said:
https://lavelle.chem.ucla.edu/forum/viewtopic.php?t=729

multiply the gas constant 8.31447 J/mol K and then divide by the gas constant 0.08206 L atm/mol K.
1 L atm = 101.33 Joules
Even though this is not wrong, is just shifting the question to why 8.31 J equals 0.082 L*atm.
You could just go directly to change the units for pressure and volume to SI units and get the answer.
## 1 atm =1.01 \times 10^5 N/m^2 ##
## 1L =10^{-3} m^3 ##
So
## 1 atm \times 1L = 101 N \cdot m ## or 101 J
 
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Consider a piston of area A moving in a cylinder with constant pressure...

Work = Force * displacement ... (1)

Pressure = Force/Area
so
Force = Pressure * Area ......(2)

sub for force in (1) gives...
Work = Pressure * Area * displacement .....(3)

then recognise that
ΔVolume = Area * displacement

so
Work = Pressure * ΔVolume
 
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