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CHEM111Week 6 Discussion QuestionsFall 20141) Which of the changes will always increase the internal energy of a system? Explain.A.The system gains energy and performs work.(q = +, w = -; so magnitude of q and w areimportant, so not always)B.The system gains energy and work is performed on it.(ALWAYSΔE = +)C.The system loses energy and performs work.(q = - , w = -, ALWAYSΔE = -)D.The system loses energy and work is performed on it.(q= -, w = +; so magnitude of q and ware important, so not always)2)In a steam engine, steam in a cylinder expands against a piston exerting 10 atm of externalpressure.The volume of the cylinder increases by 10 L and simultaneously the steam cools,losing 3000 kJ of energy to the surroundings. What is the change in energy of the steam?(101.3 J = 1 L atm)Pext= 10. atmq = -3000 kJΔE = ?Vinc= 10. LΔE = q + w = -3000 kJ + [(-10. atm * 10. L)*(101.3 J / Latm)*( 1kJ/1000 J)]ΔE= -3010. kJ