SEPARATION OF POTASSA AND SODA. 235 
Let v be the weight of the potassa in the mixture; z that 
of the soda. Let m be the weight of the mixed sulphates ob- 
tained, as stated in paragraph (1,) and n the weight of the sul- 
phate of baryta obtained as in paragraph (2,) then using 76* 
as the weight of the equivalent of baryta, and 1 1 6 as that of sul- 
19 
phate of baryta, the baryta in n will be - — n; and the oxygen 
2 9 
.2 
contained in this baryta will be — n. But the oxygen in v 
grains of potassa is and in z grains of soda is — and since 
the oxygen in the alkalies is equal to that in the baryta, 
v z 2 
Again, the sulphuric acid in n grains of sulphate of baryta 
is therefore the alkalies in the mixed sulphates (1) will 
be m — — n; that is 
29 
10 29 m- 10 n 
v-\-z—m — —n = 
29 29 
or 58 v + 58*= 58 m—20n. . . (b,) 
i • • • , , v n , 44tz. — 58m , 
combining this equation with (a,) we find z— ,and, 
2 9 
87 m — 54 n 
v= . 
29 
These formulae lead to the following rules, the analysis 
having been made as described. 
1st. For the weight of the soda. From 44 times the weight 
*1 have used throughout the equivalent numbers given by Doctor 
Thomson in the seventh edition of his System of Chemistry, in order to 
preserve uniformity in the results. 
