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Borates, tetra, sodium salts (Pentahydrate)

Synonyms & Trade Names
Borax pentahydrate, Sodium borate pentahydrate, Sodium tetraborate pentahydrate
CAS No.
12179-04-3
RTECS No.
DOT ID & Guide
Formula
Na₂B₄O₇ • 5H₂O
Conversion
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
TWA 1 mg/m3
OSHA PEL
none See Appendix G
Measurement Methods
NIOSH 0500;
OSHA ID125G
See: NMAM or OSHA Methods
Physical Description
Colorless or white, odorless crystals or free-flowing powder. [herbicide] [Note: Begins to lose water of hydration at 252°F.]
Molecular Weight
291.4
Boiling Point
?
Melting Point
392°F
Solubility
3%
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
1.82
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Noncombustible Solid
Incompatibilities & Reactivities
None reported [Note: See the reactivities & incompatibilities reported for the related substance Borax decahydrate above.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, upper respiratory system; dermatitis; epistaxis (nosebleed); cough, dyspnea (breathing difficulty)
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:No recommendation
Eyes:No recommendation
Wash skin:Daily
Remove:No recommendation
Change:Daily
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
See also
Page last reviewed: October 30, 2019