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Given the following data for liquid methanol, convert the heat capacity, thermal conductivity, and viscosity from SI units to English units:

Solution. Convert the heat capacity of methanol from units of cal/(g-°C) to corresponding English units of Btu/ ( lb-°F ) :

Note that 1.0 Btu/ ( lb-°F ) is equivalent to 1.0 cal/(g-°C). This also applies on a mole basis, i.e. 1 Btu/ ( lbmol-°F ) = 1 cal/ ( gmol-°C ) . The usual notation for heat capacity is Cp . In this book, Cp represents the heat capacity on a mole basis, while cp indicates heat capacity on a mass basis.

Convert the thermal conductivity of methanol from units of cal/(m-s-°C) to corresponding English units of Btu/ ( ft-hr-°F ) :

The usual notation for thermal conductivity is k.

C e to lb/(ft-s):

The notation for viscosity is typically µ. The kinematic viscosity, v, is defined by the ratio of viscosity to density, i.e. v = µ / ρ with units of length²/time. Finally, note that the above physical properties are strong functions of the temperature but weak functions of the pressure. Interestingly, the viscosity of a gas increases with increasing temperature, while the viscosity of a liquid decreases with an increase in temperature. These properties will be revisited in Chapter 04.