Concept explainers
(a)
Interpretation:
The average rate of heat loss should be calculated.
Concept introduction:
The amount of heat required to increase the temperature by one degree is defined as heat capacity.
The unit used to express it is thermal energy per degree temperature.
The total energy in the system due to temperature and pressure per unit of mass is known as specific enthalpy. Change in specific enthalpy is given as,
Where,
(b)
Interpretation:
The total quantity of electricity that the heater must deliver should be calculated.
Concept introduction:
The amount of heat required to increase the temperature by one degree is defined as heat capacity.
The unit used to express it is thermal energy per degree temperature.
The total energy in the system due to temperature and pressure per unit of mass is known as specific enthalpy. Change in specific enthalpy is given as,
Where,
(c)
Interpretation:
The cost of heating and total cost should be calculated.
Concept introduction:
The amount of heat required to increase the temperature by one degree is defined as heat capacity.
The unit used to express it is thermal energy per degree temperature.
The total energy in the system due to temperature and pressure per unit of mass is known as specific enthalpy. Change in specific enthalpy is given as,
Where,
(d)
Interpretation:
The effect of tub lid on the cost estimation should be explained.
Concept introduction:
The amount of heat required to increase the temperature by one degree is defined as heat capacity.
The unit used to express it is thermal energy per degree temperature.
The total energy in the system due to temperature and pressure per unit of mass is known as specific enthalpy. Change in specific enthalpy is given as,
Where,
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ELEMENTARY PRINCIPLES OF CHEM. PROCESS.
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