Magnesium sulfate decomposes into magnesium oxide (MgO) and sulfur trioxide (SO). The heptahydrate can be prepared by neutralizing sulfuric acid with magnesium carbonate or oxide, but it is usually obtained directly from natural sources. It is on the WHO Model List of Essential Medicines, the most important medications needed in a basic health system. Magnesium sulfate is a common mineral pharmaceutical preparation of magnesium, commonly known as Epsom salt, used both externally and internally. Magnesium sulfate is highly water-soluble and solubility is inhibited with lipids typically used in lotions. Lotions often employ the use of emulsions or suspensions to include both oil
Magnesium iodide Magnesium iodide Magnesium iodide is the name for the chemical compounds with the formulas MgI and its various hydrates MgI(HO). These salts are typical ionic halides, being highly soluble in water. Magnesium iodide has few commercial uses, but can be used to prepare compounds for organic synthesis. Magnesium iodide can be prepared from magnesium oxide, magnesium hydroxide, and magnesium carbonate by treatment with hydroiodic acid: Magnesium iodide is stable at high heat under a hydrogen atmosphere, but decomposes in air at normal temperatures, turning brown from the release of elemental iodine. When heated in air, it decomposes completely to magnesium