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MHT CET202312 May 2023Evening ShiftChemistryThermodynamics (C)Actual

A gas absorbs 150 ~J heat and expands by 300 ~cm ^3 against a constant external pressure 2 10^5 ~N ~m ⁻² , What is U of the system?

Options

  1. A210 ~J
  2. B90 ~J
  3. C450 ~J
  4. D-300 ~J

Correct answer

B. 90 ~J

Step-by-step solution

array rl 300 ~cm ^3=300 10⁻⁶ ~m ^3 & ~W & =- P _ ext V & =-2 10^5 ~N ~m ⁻² (300 10⁻⁶ ~m ^3 ) & =-60 ~N ~m & =-60 ~J W & =-60 ~J array Now, aligned U & = q + P _ ext V & =150 ~J +(-60 ~J ) & =90 ~J aligned

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