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75 L of liquid ethanol at 70 degrees and 55 L of liquid water at 20 degrees are to be mixed in a well-insulated flask. The energy balance for this constant pressure process is Q=delta H.
a.) neglecting evaporation and the heat of mixing, estimate the final mixture temperature.

[Andree]

Simple balance (if evaporation and mixing heat are neglected):
V(H2O)*ro(H20)*cp(H2O)*(Tk-T(H2O)) = V(Ethanol)*ro(Ethanol)*cp(Ethanol)*(T(Ethanol)-Tk)
where Tk is the final mixture temperature...
ro - densities [kg/m3]
cp - specific heat [J/kg*K]
V - volume [m3]
T- temperature [K} or [deg.C]
sorry for SI units ;-)