Sur la thermogravimétrie des précipités analytiques : Dosage du Magnésium

With the aid of the thermobalance of chevenard the authors have studied the pyrolysis of the following compounds of magnesium, which have been proposed for the gravimetric determination of this element: hydroxide, fluoride, sulphate, magnesium ammonium phosphate magnesium ammonium arsenate, magnesium ammonium carbonate, oxalate and 8-hydroxy-quinolate. Brucite is compared with the artificial product. The gelatinous nature of the precipitated fluoride prevents a definite formula being assigned to it. The series of hydrates of the sulphate is compared with that produced by the aqueous route. Precipitated ammonium magnesium, carbonate has not a definite composition. The heating curve of the oxinate differs appreciably from the literature data.