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MHT CET202121 Sep 2021Evening ShiftChemistryThermodynamics (C)Actual

Two moles of an ideal gas are expanded isothermally from 15 dm ^3 to 20 dm ^3 . If the amount of work done is -6 dm ^3 bar, find external pressure needed to obtain this work.

Options

  1. A1.2 10^5 ~Pa
  2. B3.2 ~Pa
  3. C8.1 10^4 ~Pa
  4. D2.4 ~Pa

Correct answer

A. 1.2 10^5 ~Pa

Step-by-step solution

aligned & W =- Pext. [ V ₂- V ₁ ] & -6 bar. dm ^3=- Pext [20-15] & Pext = 6 5 =1.2 bar & (1 bar =10^5 ~Pa ) & Pext =1.2 10^5 ~Pa aligned

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