Such indications are confirmed by the centigrade
alcoholmeter.
We see likewise that, for these solutions of alcohol and water, the
laws of Dalton are completely at fault, since the total pressure of the
vapors is never equal to the sum of the tensions of the two liquids,
water and alcohol.
II. Being given a solution of water and alcohol, mixed in equal volumes,
what will be the quality of the vapors emitted from it?
In other terms, do the vapors which escape from a definite mixture of
water and alcohol also contain volumes of vapor of water and alcohol in
the same proportion as the liquids?
We have discovered the following laws:
d. The quality of the vapors emitted by a mixture of water and alcohol
varies according to the alcoholic richness of the solution, but is not
in simple proportion thereto.
e. The quality of the vapors emitted by a definite mixture of water and
alcohol varies according to the temperature.
f. In a same solution of water and alcohol, it is at low temperatures
that the vapors emitted by the mixture contain the largest proportion of
alcohol.
g. The more the temperature rises the more the tensions of the two
liquids tend to become equalized.
We have been able to verify these different laws experimentally, and
to find an interesting confirmation of our general formula of maximum
tensions, in the following way:
Let us take a test tube containing a 50 per cent.
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