Potassium Alum Aluminum Sulphate

Potassium at the 25-/xg/cm2 level is added mostly with the potassium alum sizing. Note that two American-made papers of 1900 have a low potassium content, indicating that aluminum sulphate sizing probably was used. The high potassium values associated with the bismuth peaks are unaccounted for. 

Synoii3rni8.—Potassium-aluminum Sulphate Potassium Alum. 

The aluminum sulphate, after being separated from the silica, is mixed with solution of potassium sulphate the two salts unite, and on evaporation crystallize out as alum. 

But the admirable researches of Gay-Lussac and of Mitscherlich have established the fact, that in many instances, different compounds assume the same form. Thus, the following substances, and many others, take the form of the cube, tetrahedron, or regular octohedron, which are geometrically connected. Chloride of sodium (sea-salt), chloride of potassium, sal ammoniac bromide of potassium iodide of potassium sulphuret of lead fluoride of calcium bisnlphuret of iron arseniuret of cobalt sulphate of alumina and potash (alum) ammonia alum chrome alum, iron alum sesqnioxide of iron, sesquioxide of aluminum, sesquioxide of chromium. In like manner, other crystalline forms are found to be common to many different compounds, although none occurs so frequently as the cube and its congeners. 

Oleic acid Oxalic acid Pentane Petroleum ether Phosphoric acid, cone. Propyl alcohol Potassium aluminum alum Potassium bichromate Potassium bromate Potassium bromide Potassium chloride Potassium nitrate Potassium perchiorata Potassium permanganate Potassium persulphate Potassium sulphate Propargyl alcohol Propionic acid (20%) Silicone oil Silver nitrate Sodium bicarbonate Sodium bisulphate Sodium bisulphite Sodium carbonate Sodium chlorate Sodium chloride Sodium hypochlorite Sodium sulphate Stannous chloride Sulphur... 

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