Magnesium chloride

Athanor · official

Cl₂Mg · 95.21 g/mol

IUPAC name: magnesium dichloride

Also called E511, nigari

Inorganic

Open in Athanor

Drawn from its SMILES with RDKit

DangerMay be corrosive to metals · Harmful if swallowed · Causes skin irritation · Causes serious eye damage · Causes serious eye irritation · May cause respiratory irritation

Names and identifiers

IUPAC name: magnesium dichloride
Synonyms: E511, nigari, Magnesium chloride anhydrous
+ 37 more
Magnesium dichloride, MgCl2, Anhydrous magnesium chloride, DTXSID5034690, NSC-529832, 59XN63C8VM, CHEBI:6636, Chloride, Magnesium, Fibro Flex, Cramp-Z, GZE Magnesium Oil, RefChem:6461, DTXCID3014690, Bestmade Natural Products Mag Mur, 232-094-6, 02F3473H9O, Aerotex Accelerator MX, Bischofite, Bischofite (mgcl2.6h2o), E-511, INS NO.511, INS-511, Magnesia Muriatica, Magnesium chloride (Mg2Cl4), Magnesium chloride (MgCl2), MultiBic component magnesium chloride hexahydrate, NSC529832, TMT 2, MAGNESIUM CHLORIDE, ANHYDROUS, Chloromagnesite, Cl2Mg, magnesiumchloride, Magnesiumchlorid, magnesium(II)chloride, magnesium(II) chloride, magnesium (II) chloride, [MgCl2]
Molecular formula: Cl₂Mg
Empirical formula: Cl₂Mg
Molecular weight: 95.21 g/mol
Exact mass: 93.92275
CAS number: 7786-30-3
PubChem CID: 5360315
Canonical SMILES: [Mg+2].[Cl-].[Cl-]
Isomeric SMILES: [Mg+2].[Cl-].[Cl-]
InChI: InChI=1S/2ClH.Mg/h2*1H;/q;;+2/p-2
InChIKey: TWRXJAOTZQYOKJ-UHFFFAOYSA-L
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Colorless or white crystals[3]
4 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Wet Solid; Other Solid; Dry Powder; CBI; Large Crystals; Dry Powder; Other Solid; Liquid [1] EPA Chemical Data Reporting (CDR)
– DELIQUESCENT WHITE SOLID IN VARIOUS FORMS. [2] ILO-WHO International Chemical Safety Cards (ICSCs)
– Thin white to gray granules and/or flakes [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 10th ed. Volumes 1-3 New York, NY: John Wiley & Sons Inc., 1999., p. V3 2264
–shown Colorless or white crystals [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 13th ed. New York, NY: John Wiley & Sons, Inc. 1997., p. 690
Melting point: 712 °C (rapid heating)[2]
2 values
Sources disagree; from ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative.
Value As written Source
712 °Cshown 712 °C (rapid heating) [2] ILO-WHO International Chemical Safety Cards (ICSCs)
714 °C 714 °C [4] PAC Chemical Database, U.S. Department of Energy
Boiling point: 1412 °C[2]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
1412 °Cshown 1412 °C [2] ILO-WHO International Chemical Safety Cards (ICSCs)
1412 °C 1412 °C @760 [mm Hg] [4] PAC Chemical Database, U.S. Department of Energy
Density: 2.325 @25 °C[4]
3 values
3 of 3 sources agree on it (most common value).
Value As written Source
– 2.32 [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 13th ed. New York, NY: John Wiley & Sons, Inc. 1997., p. 690
– 2.3 g/cm³ [2] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown 2.325 @25 °C [4] PAC Chemical Database, U.S. Department of Energy
Solubility in water: Solubility in water, g/100ml at 20 °C: 54.3[2]
3 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– In methanol, 15.5 g/100 g @ 0 °C, 20.4 g/100 g @ 60 °C; in ethanol, 3.61 g/100 g @ 0 °C, 15.89 g/100 g @ 60 °C [3] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA15 (1991) 597
– In water, 54.6 g/100 g @ 20 °C [3] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA15 (1991) 597
–shown Solubility in water, g/100ml at 20 °C: 54.3 [2] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
–	Wet Solid; Other Solid; Dry Powder; CBI; Large Crystals; Dry Powder; Other Solid; Liquid	[1] EPA Chemical Data Reporting (CDR)
–	DELIQUESCENT WHITE SOLID IN VARIOUS FORMS.	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
–	Thin white to gray granules and/or flakes	[3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 10th ed. Volumes 1-3 New York, NY: John Wiley & Sons Inc., 1999., p. V3 2264
–shown	Colorless or white crystals	[3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 13th ed. New York, NY: John Wiley & Sons, Inc. 1997., p. 690

Value	As written	Source
712 °Cshown	712 °C (rapid heating)	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
714 °C	714 °C	[4] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
1412 °Cshown	1412 °C	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
1412 °C	1412 °C @760 [mm Hg]	[4] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	2.32	[3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 13th ed. New York, NY: John Wiley & Sons, Inc. 1997., p. 690
–	2.3 g/cm³	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown	2.325 @25 °C	[4] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	In methanol, 15.5 g/100 g @ 0 °C, 20.4 g/100 g @ 60 °C; in ethanol, 3.61 g/100 g @ 0 °C, 15.89 g/100 g @ 60 °C	[3] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA15 (1991) 597
–	In water, 54.6 g/100 g @ 20 °C	[3] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA15 (1991) 597
–shown	Solubility in water, g/100ml at 20 °C: 54.3	[2] ILO-WHO International Chemical Safety Cards (ICSCs)

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 3
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 0
H-bond acceptors: 0 computed here · PubChem 2
Rotatable bonds: 0
TPSA (Å²): 0
Formal charge: 0
Complexity: 0 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: Kh of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

Cl74.47%
Mg25.53%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: -6.37 Crippen (Wildman and Crippen 1999)
log S (water solubility): 3.58 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 8.31 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 95.21
log P ≤ 5 (Crippen): -6.37
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 0

Passes all four rules.

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Danger

Most widely reported: 1,600 company reports to ECHA. Source [5].

Corrosive
Harmful or irritant

H290May be corrosive to metals (27.6% of reports)
H302Harmful if swallowed (27.6% of reports)
H315Causes skin irritation (37.6% of reports)
H318Causes serious eye damage (27.6% of reports)
H319Causes serious eye irritation (11.8% of reports)
H335May cause respiratory irritation (10.9% of reports)

Precautionary statements: P234, P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P305+P354+P338, P317, P319, P321, P330, P332+P317, P337+P317, P362+P364, P390, P403+P233, P405, P406, P501

View all classifications (2)

[5] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 60.6% (969 of 1600) of all reports.
[5] European Chemicals Agency (ECHA) · 1,600 reports · DangerH290, H302, H315, H318, H319, H335

First aid

Fresh air, rest.[2]
Rinse skin with plenty of water or shower.[2]
Rinse with plenty of water for several minutes (remove contact lenses if easily possible).[2]
Rinse mouth.[2]

Storage

Dry.[2]

Incompatibilities

Furan-2-peroxycarboxylic acid ... Explodes when heated to 30-40 °C, or at room temp upon addition of organic or inorganic materials such as ... Magnesium chloride.[3]
A large steel evaporator used for magnesium chloride soln was shut down for maintenance. During maintenance operations a fatality occurred from atmospheric oxygen deficiency inside the evaporator. It was found later that the oxygen content in the evaporator fell from the nomral 21% to about 1% in under 24 hr, & this was confirmed in lab tests. This was attributed to very rapid rusting of the steel under warm humid conditions in the presence of traces of magnesium chloride. Further work shows that ... Presence of scale is a contributory factor.[3]
In humid environments it causes steel to rust very rapidly.[3]

Safety data sheets on the supplier’s page: Alfa Chemistry, Thermo Fisher Scientific, MP Biomedicals.

Always read the supplier’s safety data sheet before working with it.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[2]ILO-WHO International Chemical Safety Cards (ICSCs) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[3]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[4]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[5]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.