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MHT CET202123 Sep 2021Morning ShiftChemistryThermodynamics (C)Actual

A gas is allowed to expand against a constant external pressure of 2.5 bar from an initial volume ' x ' L to final volume of 4.5 ~L . If amount of work done is 5 dm ^3 bar, what is the value of ' x '?

Options

  1. A2.5 L
  2. B4.5 L
  3. C6.0 L
  4. D1.2 L

Correct answer

A. 2.5 L

Step-by-step solution

1.2 Work done =-5 bar. dm ^3 (due to expansion work done will be negative) W =- Pext [ V ₂- V ₁ ] (1 ~L =1 dm ^3 ) -5 bar- dm ^3=-2.5 bar [4.5- x ] dm ^3 4.5- x = 5 2.5 aligned & 4.5-x=2 & x=4.5-2 & x=2.5 L aligned

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