Industrial chemicals · Taylor, TX
Technical Data Sheet

Technical Data Sheet

Magnesium Hydroxide ACS

ACS

CAS Number
1309-42-8
Alliance Code
magnesium-hydroxide-acs
Generated
2026-08-31
Revision
1.1
Reviewed
2026-06-17 · Andre Taki
2D chemical structure of Magnesium Hydroxide ACS
Structure · PubChem
Last reviewed 2026-06-17 by Andre Taki, DOT Hazmat Specialist.

Identity & Composition

Product Name
Magnesium Hydroxide ACS
Alliance Code
magnesium-hydroxide-acs
Grade
ACS
Concentration
CAS Number
1309-42-8PubChem
Formula
H2MgO2PubChem
Molecular Weight
58.320PubChem
Product Type
pure_substance

Specifications

TestSpecificationTypicalMethodSource
Assay [Mg(OH)2]95.00 - 100.5 %97.75 %Supplier specification
Arsenic (As)3 ppm max0.1 ppmSupplier specification
Calcium (Ca)1.50 % max0.05 %Supplier specification
Carbonate (CO3)To pass testPasses testSupplier specification
Heavy metals (as Pb)0.01 % max0.001 %Supplier specification
Loss on drying @ 105 C2.00 % max0.4 %Supplier specification
Loss on ignition30 - 33.00 %31.50 %Supplier specification
Identification (magnesium)To pass testPasses testACS identification test - flame reaction and precipitation with ammonium phosphateInterpreted
Insoluble in dilute hydrochloric acid0.02 % max0.005 %Gravimetric - dissolve in dilute HCl, filter, ignite residueInterpreted
Chloride (Cl)0.03 % max0.005 %Turbidimetric comparison with AgNO3 against chloride standardInterpreted
Sulfate (SO4)0.10 % max0.01 %Turbidimetric comparison with BaCl2 against sulfate standardInterpreted
Iron (Fe)0.02 % max0.002 %Colorimetric, 1,10-phenanthroline (or ICP-OES)Interpreted
Ammonium hydroxide precipitate (as R2O3)0.02 % max0.005 %Gravimetric - NH4OH precipitation, ignition to mixed oxidesInterpreted

Specification values are guaranteed limits. Typical values are representative of production lots and are not guaranteed. Lot-specific certificates of analysis ship with every order.

Available GradesSame CAS, alternate grades and concentrations

GradeConcentrationTypical AssaySKUTDS
This grade ACScurrentcurrent
magnesium-hydroxide-technicalView TDS →

Typical assay shown is the rolling-window mean from the sibling product's most recent lots. Grade selection drives downstream end-use — verify the sibling grade matches your specification before substitution.

Physical & Chemical Properties

PropertyValueSource
AppearanceDry Powder, Liquid; Pellets or Large Crystals; Liquid; Water or Solvent Wet Solid; Dry Powder; Other SolidPublished reference
FormSolidPublished reference
OdorOdorlessPublished reference
pHpH = 9.5-10.5 (aqueous slurry)Published reference
Density2.36 g/mLPublished reference
Boiling Point350Published reference
Melting Point350 °C (decomposes)Published reference
Flash PointN/APublished reference
Solubility (water)Practically insoluble in water and in ethanolPublished reference

Regulatory & Transport

DOT / 49 CFR

UN Number
Not regulatedAdjudicated
Hazard Class
Not regulatedAdjudicated
Packing Group
Not regulatedAdjudicated
Proper Shipping Name
Not regulatedAdjudicated

GHS / OSHA HazCom 2012

Signal Word
Not regulatedAdjudicated
H-Codes (Hazard Statements)
no canonical
P-Codes (Precautionary Statements)
no canonical

Occupational Exposure Limits

OSHA PEL (29 CFR 1910.1000)
no canonical
ACGIH TLV
no canonical
NIOSH REL
no canonical
NIOSH IDLH
no canonical

Transport descriptions reflect 49 CFR 172.101 lookup at time of publication. Sourced data: ECHA CLP Annex VI for harmonised classifications, NIOSH Pocket Guide for REL/IDLH, OSHA Z-Tables for PEL. Always verify against the latest regulatory text before shipment-critical decisions.

Supplier Qualification Packet

One zipped download containing the TDS, SDS, latest lot COA (when available), and a fresh Letter of Continuing Guaranty for Magnesium Hydroxide ACS. Every file included is SHA-256 hashed and listed in a manifest your QA team can audit.

Download audit packet

Applications

  • Acid neutralizationmagnesiaspecialties.com
  • Flame retardant and smoke suppressant in plasticsmagnesiaspecialties.com
  • Acid scavenger in elastomersmagnesiaspecialties.com
  • Production of magnesium salts, ceramics, and specialty applicationsmagnesiaspecialties.com

Applications are drawn from published manufacturer and supplier documentation; each is sourced. Suitability for a specific use is the buyer's to confirm.

Storage & Handling

Recommended Storage
Store in a dry place; exposure to moisture may cause cakingmagnesiaspecialties.com
Handling Precautions
Use standard chemical PPE — splash goggles, gloves, lab coat. Refer to SDS for hazard-specific PPE requirements.Class-level guidance — not product-specific; the SDS controls.
Incompatibilities
moisturemagnesiaspecialties.com
Shelf Life
Consult Technical Services for product-specific shelf life

For full hazard, PPE, and emergency response guidance, refer to the Safety Data Sheet (SDS) for this product. The SDS controls in all cases where guidance differs.

Packaging & Logistics

Shipping Description (US DOT)

Not regulated for transport.

Confirm against shipping documents and carrier requirements before tender.

NMFC Class
70

Revision History

Last reviewed 2026-06-17 by Andre Taki, DOT Hazmat Specialist.

VersionDateChangeTrigger
1.12026-06-17Canonical data re-verified: 3 fields updated against independent vendor SDSs, CLP Annex VI, 49 CFR, and OSHA HazCom 2024 (GHS classification, hazard/precautionary codes, signal word, physical properties as applicable).
  • countryOfOrigin· canonical adjudication / reground (coa.data_provenance)
  • dotSubsidiaryHazardClass· canonical adjudication / reground (coa.data_provenance)
  • hsCode· canonical adjudication / reground (coa.data_provenance)
canonical_change
1.02026-05-20Initial URL-first TDS published from canonical chemistry registry.initial

This Technical Data Sheet is provided for technical reference. The Safety Data Sheet (SDS) controls in all cases where guidance differs. Values reflect Alliance Chemical canonical data at time of generation; subsequent revisions are recorded in the Revision History above.