Constituent
Name
Magnesium(II) sulfate hydrates
Official name
Magnesium(II) sulfate hydrates
Family
ionic solid
Class
normal salt
Compound type
sulfate
Comments
Magnesium sulfate hydrates occurs as minerals: Kieserite (monohydrate), Starkeyite (tetrahydrate), Pentahydrite (pentahydrate), Hexahydrite (hexahydrate), Epsomite (heptahydrate) and Meridianite (undecahydrate).
Constituent abundance in material
Relevance
main - major
Arrangement
inclusion
Mass fraction
20.0 $\pm$ 0.1
Chemical composition
Formula
$Mg^{2+} \cdot SO_4^{2-} \bullet n(H_2O)$
Chemical formula
MgSO4•n(H2O)
Elemental formula
(Mg2+) S (O)3-13 (O-)2 (H)2-22
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Mole fraction Isotope mole fraction State Relevance
$Mg^{2+}$ Magnesium(II) cation element 1 0.125 1 constituent cation main
$(SO_4)^{2-}$ Sulfate anion chemical function 1 0.125 1 anionic radical main
$H_2O$ Water molecule 1 - 11 0.75 $\pm$ 0.625 1 hydration main
Composition comments
the is a dozen of different hydrates with hydration number between 1 and 11
Chemical functions
  Function Number Relevance
$(SO_4)^{2-}$ 1
$R-OH$ 2 main
Chemical bonds
  Bond Number Relevance
$\cdot Mg^{2+} \cdot O^{-}-$ 2
$-O \dots H-$ 2n
$-O-H$ 2 main
$\dddot - \dddot - \dddot - S \dddot - O^{-1/2}$ 4
Class
normal salts (07)
Type
hydrated simple normal salts (07.04)
Phase type
crystalline
Crystal system
various
Crystal class
various
Crystal class symbol
various
Crystal spacegroup
various
Comments
The structure depends on degree of hydration
Molar mass
138.38 (n=1) - 336.545 (n=11) $g/mol$
Density
2.445 (n=1) - 1.512 (n=11) $g/cm^3$
Refringence type
various
Color
colorless
Diaphaneity
transparent to translucent
Luster
vitreous