Shweta Thakur posted an Question
July 24, 2020 • 18:57 pm 30 points
  • IIT JAM
  • Chemistry (CY)

Plz explain the encircled b part deal gas expands isotherr 25c from a volume of 10

S226837y Ex 51 (a) What is the change in entropy of the gas? (i) (ip) What is the change in tibly by simply opening a stopcith the surroundings. (i) W=0. (Pext=0) as we expect entropy to increase in an irreversible proce (iv) ASu =0. e entropy of the system plus surroundings increases by 576/K

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    Priyanshu kumar Best Answer

    read this example- Imagine an ideal gas confined to a 1-L flask at 1 atm pressure. The flask is connected by a closed stopcock to another 1-L flask, which is evacuated. Now suppose the stopcock is opened while keeping the system at a constant temperature. Then ,the gas will spontaneously expand into the second flask until the pressure is 0.5 atm in both flasks. During this constant temperature, or isothermal expansion into a vacuum, the gas does no work (w = 0) and no heat is transferred between the system and surroundings (q = 0). 

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    now got it shweta??

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    S is a state function so it doesn't change...as Pext is 0 so no work done also no heat is exchange between system and surroundings...delta S surroundings also equal to 0...

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    thanks 😊

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    sir cp is also equal to change in enthalpy of product -reactnt .

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    yes Shweta heat capacity at constant pressure Cp= DelH/ DelT

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    also called kirchoffs law at constant pressure

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    ok sir

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    Priyanshu kumar

    wait shweta...

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    yes sir

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    shweta...i explained this on copy so that you can easily understand...wait for some tym...

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