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MHT CET202415 May 2024Evening ShiftChemistryThermodynamics (C)Actual

A system performs mechanical work equal to 15 kJ and looses 2 kJ of heat to surrounding. What is the change in internal energy of a system?

Options

  1. A-15 kJ
  2. B-17 kJ
  3. C13 kJ
  4. D19 kJ

Correct answer

B. -17 kJ

Step-by-step solution

W =-15 ~kJ , Q =-2 ~kJ According to the first law of thermodynamics, U = Q + W =-2+(-15)=-17 ~kJ .

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