Page:Outlines of Physical Chemistry - 1899.djvu/251

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From the thermo-chemical point of view all the other actions can be neglected.

- The effect due to the first cause would be x times the difference between the heats of neutralisation of sodium nitrate and of sodium sulphate, that is, — 2*072 x.

The value of the effect due to the second cause would be the same as (1 — x) times the effect produced by the

Now, Thomsen has found that

��action of = sulphuric acid on 1 of sodium sulphate.

j. — — x

��[ft£H 2 S0 4 aq, £Na 2 S0 4 aq] = 5— 1-65 Cal.

From this we deduce :

��x

��= - (1 - x) -i — x — 1-65 Cal. 1 — x

The result of the calorimetric determination of this reaction is an absorption of 1*752 Cal., so that we can

write

x

x (- 2-072) _ (1 _ «) 1 ~ x — 1-65 = - 1-752. 1 — x

The solution of this equation gives for the value of x 0*665, from which we deduce

If now the reacting products be mixed in other pro-

�� �