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MHT CET202121 Sep 2021Morning ShiftChemistryThermodynamics (C)Actual

A gas is allowed to expand in an insulated container against a constant external pressure of 2.5 ~atm from 2.5 ~L to 4.5 ~L , the change in internal energy of the gas in joules is

Options

  1. A-836.3 ~J
  2. B-1136.2 ~J
  3. C-450 ~J
  4. D-506.5 ~J

Correct answer

D. -506.5 ~J

Step-by-step solution

q =0 due to insulated container From first law of thermodynamics, aligned & U = q + w & W =- Pext [ V ₂- V ₁ ] & =-2.5[4.5-2.5] atm - L & =-2.5 2 ~atm - L & =-5 101.3 ~J & =-506.5 ~J & U = q + w & =0-506.5 & =-506.5 ~J aligned

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