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MHT CET202526 Apr 2025Morning ShiftChemistryThermodynamics (C)Actual

Calculate the change in internal energy of the system if work done by the system is 18 joule and absorbs heat 50 joule in a particular reaction.

Options

  1. A20 J
  2. B32 J
  3. C48 J
  4. D68 J

Correct answer

B. 32 J

Step-by-step solution

The change in internal energy, U , is determined by the First Law of Thermodynamics: U = q + w , where q is the heat absorbed and w is the work done on the system. Given q = +50 J and w = -18 J (indicating work done by the system), substitute into the equation: U = 50 J + (-18 J ) = 32 J . Thus, U = 32 J .

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