Ebullioscopic or Boiling-point method

Statical Method.—The most convenient form of apparatus for determining molecular weight by this method is Beckmann s boiling-point apparatus shown m Fig. 32. 

It consists of a boiling-tube, thiough the bottoni-stout platinum wire is sealed, which is intenclcd 

This thei-ii ometer is similar in nonstt-tj(.j.jQj to that u.secT. for- freezing-point rumina- 

The temperature being constant, a pellet (oT—o 2 gram) of fused naphthalene is caiefully weighed and dropped into the boil-mg-tiibc th.rough the condenser without intenupting the boiling. T hesc pellets are conveniently made in a small bullet-mould. 

When the observations are complete, the apparatus is allowed to cool and the weight of benzene ascertained by weighing the boiling-tube and benzene. 

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