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Three moles of an ideal gas are compressed isothermally from 60 L to 20 L using constant pressure of 5 atm. Heat exchange Q for the compression is - Lit. atm.
200
Isothermal, ideal gas ⇒ ΔU = 0 ⇒ Q = −W
Irreversible (constant external pressure): W = -Pext(V2 - V1)
= -5(20 - 60) = 200 L atm
∴ Q = −200 L atm (heat is released) ⇒ blank = 200
Answer: 200
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