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Magnesium Sulfate Melting Point

magnesium sulfate melting point

The melting point of magnesium sulfate, or MgSO4, is -122°C. It is soluble in water and is used as a laxative, as well as in some industrial processes, including tanning, explosives, fertilizer, paper making, porcelain, printing dyes and other applications.

It is also an excellent desiccant.

In agriculture, it is used to increase the soil’s magnesium and sulfur content. It is also used as a coagulant in making tofu and can be found in some commercially available bath salts, as it is believed that the addition of magnesium sulfate to a bath helps soothe rheumatoid arthritis and muscle pains.

Medically, it is used as a supplement to low levels of magnesium in the blood and to forestall seizures associated with pregnancy. It is a component of many double salts (ionic salts with more than one cation or more than one anion).


Ingestion and skin exposure to high concentrations of magnesium sulfate can cause poisoning in some people. This is particularly true of children, but can be severe in older people who do not have healthy kidney function.

Poisoning is usually accompanied by nausea, vomiting and stomach pain. Other symptoms may include weakness, sweating, redness or a tingly feeling.

Symptoms can be reversed with IV administration of calcium gluconate and mannitol forced diuresis. The treatment for acute magnesium toxicity is similar to that of intravenous potassium chloride.

Besides being an essential component of the body’s neurotransmitters and enzyme systems, magnesium is important in plants as it is involved in photosynthesis. Green plants use the magnesium ion in their chlorophyll to absorb light and turn it into chemical energy, which they then use to power a wide variety of functions.