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Question 2.12: For the flow calorimeter just discussed, the following data ...

For the flow calorimeter just discussed, the following data were taken with water as the test fluid:

Flow   rate  =  4.15  g . s^{−1}     t_{1} = 0°C          t_{2} = 300°C             P_{2} = 3  bar

Rate of heat addition from resistance heater = 12,740 W

The water is completely vaporized in the process. Calculate the enthalpy of steam at 300°C and 3 bar based on H = 0 for liquid water at 0°C.

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If Δz and Δu^{2} are negligible and if W_{s}  and  H_{1} are zero, then H_{2}= Q, and

H_{2} = \frac{12,740  J⋅s^{-1} }{4.15  g⋅s^{-1}} = 3070  J⋅ g^{-1}            or              3070  kJ⋅ kg^{-1}

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