278 
MUTUAL DECOMPOSITION. 
Mutual de- 
composition 
of the insolu 
ble neutral 
salts, &c. 
as a certain limit; beyond which there was no longer any 
action. 
Lastly, the sulphate of potash, and the sulphate of soda 
alone and perfectly neutral, redacted likewise upon the carbo- 
nate of barytes, and produced on one part sulphate of barytes, 
and on. the other, the sub-carbonate of potash or of soda, which 
remained in solution together with the portion of the sulphate 
which resisted the decomposition. 
A comparative experiment was made on these two salts 
similar tc experiment C. 
Experiment E. Twenty grammes of crystallised sulphate 
of soda, and ten grammes of sulphate of potash, also crystallised, 
were separately dissolved in 200 grammes of water: and each so- 
lution remained in ebullition during two hours, together with 
20 grammes of carbonate of barytes. The sulphate soda produced 
IO i;o grammes of sulphate of barytes, and the sulphate of 
potash, 9*8/0. The quantities of the sulphate of soda and of 
the sulphate of potash used in this experiment were calculated 
according to the analysis of M. Berard, and each one ought 
to contain 4'433 grammes of real sulphuric acid; now the 
sulphate of soda lost 3 484 grammes which combined with 
the barytes, and only IO 949 grammes remained in the liquid. 
The sulphate of potash only precipitated 34 88 grammes, and 
consequently, ought to yet retain 1245, whence it follows that 
the relation between the quantities of sulphurate acid retained 
by the potash and the soda, under thdse circumstances, differ- 
very little from the quantities of the sulphate of barytes, de- 
composed by the sub-carbonates of the same basis. (Experi- 
ment. Cj 
The re-action of the insoluble carbonates and soluble salts, 
of which the acids can form with the basis of these carbonates 
insoluble salts, is equally general with that of the soluble 
carbonates on the insoluble salts. I have verified this fact by 
direct experiments on a great part of the known salts which 
unite these conditions, and the following table contains the 
results 
