A gas occupies 2 litre at STP. It is provided 58.63 joule heat so that its volume becomes 2.5litre at 1 atm. Calculate change in its interna energe

Answer

5 J

Explanation

Work done `= -P xx dV = 1 xx (2.5 - 2.0)`
`=-0.5` litre - atm
`= - (0.5 xx 1.987 xx 4.184)/(0.0821) =` joule `=-50.63 J`
`:.` Work is carried out at constant P and thus irreversible. From I law of thermodynamics
`:. Q = Delta U - W , 58.63 = Delta U + 50.63`
`:. Delta U = 8` joule