Magnesium sulfate

Structural formula
name magnesium sulfate
other names epsom salt
sum formula mg S O 4
CAS number 7487-88-9
short description colorless solid
mol mass 120.37 g mol
state of aggregation firmly
density 2.66 g/cm ³
melting point 1124 °C (decomposition)
boiling point --
Steam pressure ? Pa (x °C)
solubility well in water solubly
MgSO 4: 269 g/L (0 °C)
MgSO 4·7H 2 O: 710 g/L (20°C)
safety references
of Gefahrensymbole
R and S-sentences

of R: -
S: -

As far as possible and common, SI-UNITs are used. If not differently notes, the indicated data apply with standard conditions.

Magnesium sulfate is a strongly hygroscopic connection, which is used mainly for the drying process and as magnesium - fertilizers.


magnesium sulfate, strongly hygroscopic solid with bitter taste is more colorless, more smellless. Several hydrates exist, from those the most important magnesium sulfate heptahydrate MgSO 4·7H 2 O (epsom salt or Epsomit) is.


magnesium sulfate can be made of magnesium and sulfuric acid after the following reaction equation:
<math> \ mathrm {mg + H_2SO_4 \ rightarrow H_2 + MgSO_4}< /math>
Further it develops during the conversion of magnesium oxide or Magnesiumhdroxid with sulfuric acid and following evaporation of the water and/or. Drying process:
<math> \ mathrm {MgO + H_2SO_4 \ rightarrow H_2O + MgSO_4}< /math>
<math> \ mathrm {mg (OH) _2 + H_2SO_4 \ rightarrow 2H_20 + MgSO_4}< /math>


magnesium sulfate is used as source of magnesium for plants in fertilizers. Because of its hygroscopic character it is used in organic chemistry for the drying process of materials. In addition one does not give to the liquid which can be dried as much water-free magnesium sulfate, to it to any more liquid. The magnesium sulfate can be filtered off afterwards. Further ranges of application are under the keyword Epsomit.

Please you consider the reference to health topics!

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