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MHT CET202123 Sep 2021Evening ShiftChemistryThermodynamics (C)Actual

A system given out x J of heat and does y J of work on it's surrounding. What is the internal energy change?

Options

  1. A-x-y ~ J
  2. By-x ~ J
  3. Cx-y ~ J
  4. Dx+y ~ J

Correct answer

A. -x-y ~ J

Step-by-step solution

q =- xJ Heat released by system (-) ve w =- yJ Work done by system (-) ve From first law of thermodynamics. aligned & U = q + w & =- x - y J aligned

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