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COMEDK2021ChemistryThermodynamics (C)

The change in the energy of system if 500 cal of heat energy are added to a system and system does 350 cal of work on the surroundings will be

Options

  1. A-150 cal
  2. B+150 cal
  3. C+850 cal
  4. D-850 cal

Correct answer

B. +150 cal

Step-by-step solution

According to the first law of thermodynamics, the change in internal energy U of a system is given by the equation U = Q - W , where Q is the heat added to the system and W is the work done by the system. Given values are Q = +500 cal (heat added to the system) and W = +350 cal (work done by the system). Substituting these values into the equation: U = 500 cal - 350 cal U = +150 cal Answer: +150 cal

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