Question

Argon often used to fill incandescent and fluorescent light bulbs to prevent oxygen from corroding the hot filament. A small light bulb (volume 75 ml) is filled with argon, and

when the bulb is turned on the pressure and temperature inside reach 110 kPa and 70°C, respectively. Once the light is turned off the argon reaches thermal equilibrium with the ambient air at 20°C. Find: The heat lost as the argon cools to ambient temperature (in Joules) ) The total entropy generation during the process, in kJ/K

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