TH201 : Determination of Partial Molar Enthalpies

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TH201 Determination of Partial Molar
Enthalpies by Adiabatic
Calorimeter
Aim To determine the heat of mixing and partial
molar enthalpies of two components
using adiabatic calorimeter
Theory Heat of mixing
Adiabatic Calorimeter
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Theory
For a heating coil
For known amount of heat, Q (Joules) is supplied
to calorimeter containing water if ?T is the
observed temperature change, then
Combining the above equations by assuming
perfectly adiabatic conditions
The heat evolved due to mixing
The heat of mixing ?hm is given by
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Experimental procedure

• Calculate the water equivalent of thermometer.
• Find out the specific heat of pure components.
• Measure the change in temperature ?Tm and
  correspondingly find out the heat of mixing and
  the specific heat of mixture.
• Plot a graph of ?hm vs mole fraction of one of
  the components.
• Find out the partial molar enthalpies of
  components at given mole fractions

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Calculation of Partial Molar Enthalpies