Question

2. Write and simplify the closed-system energy balance for each of the following processes, and state whether heat and work terms positive or negative or zero. Begin by defining the are system. Indicate why each term in the energy balance is neglected. The contents of an agitated, sealed flask are heated from 25°C to 80 °C.. a. b. A chemical reaction takes place in a closed adiabatic (perfectly insulated) rigid container. Repeat part (b), only suppose that the reactor is isothermal rather than adiabatic and that when the reaction was carried out adiabatically the temperature in the reactor increased. d. Water is pumped from the bottom of a well 20 m below the ground through a 2-cm ID pipe, through the water heater and to your shower 1 m above the ground. The shower head has a cross-sectional area of 1 cm2. C.

Answer 1

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