Questions and answers on the essentials of medical chemistry / By Lawrence Wolff.

  • Wolff, Lawrence.
Date:
1888
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Licence: Public Domain Mark

Credit: Questions and answers on the essentials of medical chemistry / By Lawrence Wolff. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    What is magnesium hydrate? Magnesium hydrate or hydroxide Mg(OII)2 is the precipitate resulting when a solution of a magnesium salt is decomposed by the hydrate of potassium or sodium ; in suspension with water it is known as milk of magnesia. What is magnesium chloride? A very deliquescent salt MgCl,, present in many mineral springs, and in some impure grades of table salt. What is magnesium sulphate? Magnesium sulphate, Epsom salt MgS04 + 7Aq, found in sea- water and in a number of mineral springs. It crystallizes in four-sided rhombic prisms, is readily soluble in water, has a bitter, saline taste, and finds much use as an aperient. Which are the principal phosphates of magnesium ? The tri-magnesium phosphate Mg3(Po4)2 in bones, the mono- magnesium phosphate MgHPo4+7Aq present in the urine; when it meets ammonium compounds, it forms the ammonium-magne- sium phosphate MgNH4P04 + 6Aq, also termed triple-phos- phate. MgHPO, -f- NH4HO = MgNH4P04 + H20. What is the cause of the formation of triple-phosphate in the urine, and what is its significance? When urine is decomposed by putrefactive change ammonium carbonate is formed, CON,H4+ H20 = (NH4)2COa; this with magnesium phosphate yields ammonium-magnesium phosphate, 2MgHP04 + (KHJ2C03 = H2COs+ 2MgNH4P04, which separates out in microscopic prismatic crystals resembling coffin lids. If these occur persistently, the liability to forma- tion of fusible or triple-phosphate calculi arises. Which are the principal carbonates of magnesium ? Neutral magnesium carbonate MgC03, which occurs in nature as magnesite. The magnesii carbonas of the Pharmacopoeia is a mixture of magnesium carbonate with magnesium hydrate (MgC03)4Mg(OH)2 -+• 5H20 ; a white voluminous powder, usually offered in the market as light-white cubes. This, when suspended