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AP EAMCET202125 Aug 2021Morning ShiftChemistryThermodynamics (C)Actual

An ideal gas expanded irreversibly against 10 bar pressure from 20 ~L to 30 ~L . Calculate Q if the process is isoenthalpic. 1 ~L bar =100 ~J

Options

  1. A0
  2. B100 ~J
  3. C-100 ~J
  4. D10 ~kJ

Correct answer

D. 10 ~kJ

Step-by-step solution

According to thermodynamics irreversibly expanded system work. W_ irr =-p_ opp. (V₂-V₁ )...(i) Ideal gas expanded irreversibly =10 bar aligned & V₂=30 ~L & V₁=20 ~L aligned Put all value in Eq. (i), we get aligned W_ irr & =-10 bar (30-20) L & =-9.869 ~atm 10 ~L aligned aligned & =-9999.76 ~J & =-10 ~kJ aligned Since, for expanded irreversibly, H=0 ( H=0 i.e. isoenthalpic process) aligned & Q=-W_ irr & Q=-(-10 ~kJ ) & Q=10 ~kJ aligned Hence, Q value of isoenthalpic process is 10 ~kJ .

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