501 
1898-99.] Sulphuric Acid and Sulphates in Solution. 
which was made 0*2 normal with respect to sulphuric acid and 
0*1 normal with respect to potassium sulphate. We therefore 
have the following concentrations of acid, acid sulphate and neutral 
sulphate at equilibrium : — 
^ lOpO ~ = gram, equivalent H 2 S0 4 per litre. 
0-2 -0-1600 = 0-0400 „ KHS0 4 „ 
0-1 -0-0400 = 0-0600 „ K 2 S0 4 
This simple calculation has been performed in every case, and in 
the next three tables the concentrations of the free acid, neutral 
and acid sulphates in the various solutions are given. The 
numbers in the first column indicate the concentrations of that 
substance, either acid, neutral sulphate, or acid sulphate, the 
amount of which was varied in the different experiments of 
each series. 
First Series. 
Concentration of K 2 SO 4 = 0-l. 
h 2 so 4 
Free Acid. 
Neutral Sulphate. 
Acid Sulphate. 
0-025 
0-0154 
0-0904 
0-0096 
0*05 
0-03295 
0-08295 
0-01705 
o-i 
0-0718 
0-0718 
0-0282 
0-2 
0-1600 
0-0600 
0-0400 
0'35 
0*2972 
0-0472 
0-0528 
Second Series. 
Concentration of H 2 SO 4 = 0*l. 
k 2 so 4 
Free Acid. 
Neutral Sulphate. 
Acid Sulphate. 
0-4 
0-0391 
0-3391 
0-0609 
0-2 
0-0543 
0-1543 
0-0457 
0*1 
0*0718 
0-0718 
0-0282 
0-05 
0-0847 
0-0347 
0-0153 
0-025 
0-09186 
0-0169 
0-00814 
Third Series. 
khso 4 
Free Acid. 
Neutral Sulphate. 
Acid Sulphate. 
0-2 
0-1252 
0-1252 
0-0748 
0-15 
0-1011 
o-ioii 
0-0489 
o-i 
0-0718 
0-0718 
0-0282 
0-05 
0-0412 
0-0412 
0-0088 
0-025 
0-02250 
0-02250 
0-00250 
These are, however, the total concentrations of the three sub- 
stances, and as the equilibrium, the nature of which it was sought 
to determine, is that existing between the undissociated portions of 
each, we must know the value of their degrees of dissociation. As 
