Magnesia alba

The acid humor arising from food, and magnesia alba. 

Black, Joseph, Experiments upon Magnesia Alba, Quicklime, and Other... 

At this time is was believed that when carbonates were calcined they combined with an acrid principle from the fire to foim caustic alkalies. In 1755, however, Dr. Joseph Black (26) of Edinburgh published a famous treatise entitled, Experiments upon Magnesia Alba, Quicklime, and some other Alkaline Substances, in which he proved that carbonates lose weight during calcination and that the substance... 

Dr. Joseph Black of Edinburgh recognizes magnesia alba to be distinct from lime. 

Joseph Black (1728-1799) conducted an important series of experiments during work on his doctoral dissertation in medicine. Black was searching for a material to dissolve kidney stones. He chose magnesia alba (magnesium carbonate), but... 

Black decided that the gas given off in the reaction between magnesia alba and acid was similar to one described by van Hel-mont. He coined the term fixed air to indicate that this gas was fixed or trapped in magnesia alba. Black also recognized that fixed air was the same gas produced in respiration, combustion, and fermentation. Today, we know Black s fixed air was car-... 

Joseph Black, upon completion of his study on magnesia alba, received his medical degree. He published very little after this study. Black taught at universities in Glasgow and Edinburgh, and continued to do solid research, which he presented in his lectures. One area in which he did important work was heat and the latent heat of steam. His work in this area inspired one of his students James Watt to apply Black s ideas in making improvements to the steam engine. 

Black, Magnesia Alba, Source Book, 86 Alembic Club Reprint, 22. 

In an important paper entitled Experiments upon magnesia alba) quicklime, and other alcaline substances, published in 1755,1 J. Black first made clear the relations between caustic alkali and mild alkali that is, between the alkali hydroxides and alkali carbonates. These relations were not understood by the early chemists. They believed the mild alkalies and alkaline earths—that is, the carbonates of the alkalies and alkaline earths—to be elementary substances that the causticity of lime was due to the union of fire-matter or phlogiston with elemental chalk and the conversion of mild alkali into caustic alkali, with the simultaneous regeneration of chalk, by boiling the former with caustic lime, was due simply to the transfer of the phlogiston or fire-matter from the lime to the mild alkali. Otherwise expressed Quicklime=Chalk-f Fire-matter. J. Black proved this hypothesis to be untenable. H. L. Duhamel du Monceau 2 had shown nine years earlier in a memoir Diverses experiences sur la chaux, that limestone loses weight when calcined and regains it little by little on exposure to air. 

J. Black, Experiments and Observations, Physical and Literary, Edinburgh, 2. 157, 1755 Experiments upon Magnesia alba, Quicklime, and other Alcaline Substances, Edinburgh, 1777 Alembic Club Reprints, 1, 1893 Lectures on the Elements of Chemistry, Edinburgh, 1803. 

Magnesium Basic Carbonate (Magnesia Alba). Add a sodium carbonate solution to a magnesium sulphate or chloride solution heated to 50 °C up to complete precipitation. What is the composition of the precipitate Filter off the latter, wash it with water, and dry it in a drying cabinet at 100-150 °C. Heat the filtrate up to boiling. What do you observe Write the equations of the reactions. 

Neutral Tartrate of Magnesia—2 MgO, C0 II4 OlW 8 HO—obtained by digesting excess of magnesia alba in dilute tartaric acid. Crystalline crusts... 

Experiments upon Magnesia Alba, Quicksilver, and some other decline substances, 1755, being the cliemie il part of his Latin thesis printed in 1754. 

Magnesium Carbonate(also called Magnesite or Magnesia Alba), MgCOjj mw 84.32, col rhmbpowd, mp dec 350°, d 3.04 (Ref 5,p 505). (See also Spec MIL-M- 11361A)... 

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