Page 193 - Handbook of Hazardous Chemical Properties
P. 193
FLUOSILICIC ACID 183
Physical and Chemical Properties - Physical State at 15 "c and 1 am.: Gas; Molecular Weight:
37.99; Boiling Point at 1 m.: -306, -188, 85; Freezing Point: -362, -219, 54; Critical Temperature:
-199.5, -128.6, -144.6; Critical Pressure: 809.7, 55.08, 5.58; Specific Gravity: 1.5 at -188, (liquid);
Vapor (Gas) Specific Gravity: Not pertinent; Ratio of Specific Heats of Vapor (Gar) 1.362; Latent Heat
:
of Vaporization: 71.6, 39.8, 1.67; Heat of Combustion: Not pertinent; Heat of Decomposition: Not
pertinent.
Health Hazards Information - Recommended Personal Protective Equipment: Tight-fitting chemical
goggles, special clothing, not easily ignited by fluorine gas; Symptoms Following Exposure: Severe
burning of eyes, skin and respiratory system. The burns may develop slowly after exposure; General
Treafment for Exposure: Flush all affected parts with water for at least 15 min. Do not use ointments.
Administer artificial respiration and oxygen if required; Toxicity by Inhalation (Threshold Limit Value):
1 ppm; Short-Tern Inhalation Limits: 0.5 ppm for 5 min.; Toxicity by Ingestion: Not pertinent; Lute
Toxicity: Severe burns may develop slowly after exposure; Vapor (Gas) Im'tant Characteristics: Vapors
cause severe irritation of eye and throat and can cause eye and lung injury. They cannot be tolerated
even at low concentrations; Liquid or Solid Imkmt Characteristics: Severe skin irritant. Causes second-
and third-degree burns on short contact and is very injurious to the eyes; Odor l7ireshold 0.035 ppm.
Fire Hazards - Flash Point : Not flammable; Flammable Limits in Air (%I): Not flammable; Fire
Extinguishing Agents: Not pertinent; Fire Extinguishing Agents Not To Be Used: Do not direct water
onto fluorine leaks; Special Hazards of Combustion Products: Toxic gases generated in fires involving
fluorine; Behavior in Fire: Dangerously reactive gas. Ignites most combustibles; Ignition Temperature
: Not flammable; Electrical Hazard: Not pertinent; Burning Rate: Not pertinent.
Chemical Reactivity - Reactivity with Waer: Reacts with water to form hydrogen fluoride, oxygen and
oxygen difluoride; Reactivity with Common Materials: Reacts violently with all combustible materials,
except the metal cylinders in which it is shipped; Stability During Transport: Stable; Neutralizing
Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of
Polymerization: Not pertinent.
FLUOSILICIC ACID
Chemical Designations - Synonyms: Fluorosilicic acid, Hexafluosilicic acid, Hydrofluosilicic acid,
Hydrogen hexafluorosilicate, Sand acid, Silicofluoric acid; Chenical Fornula: H,SiF6-H,0.
Observable Characteristics - Physical State (as shipped): Liquid; Color: Transparent, straw colored,
colorless; Odor: Acrid, sharp.
Physical and Chemical Properties - Physical State at 15 "c and 1 atm. : Liquid; Molecular Weight:
144.09 (solute only); Boiling Point ut 1 am.: (water) -212, - 100, - 373; Freezing Point: (typical)
-24 to -4, -31 to -20,242 to 253; Critical Temperature: Not pertinent; Critical Pressure: Not pertinent;
Specific Gravity: (approx.) 1.3 at 25 "C, (liquid); Vapor (Gas) Specific Gravity: Not pertinent; Ratio
of Specipc Heats of Vapor (Gas): Not pertinent; Latent Heat of Vaporizm'on: Not pertinent; Heat of
Combustion: Not pertinent; Heat of Decomposition: Not pertinent.
Health Hazards Information - Recommended Personal Protective Equipment: Rubber gloves, safety
glasses, protective clothing; Symptoms Following Exposure: Inhalation of vapor produces severe
corrosive effect on mucous membrane. Ingestion causes severe bums of mouth and stomach. Contact
with liquid or vapor causes severe burns of eyes and skin; General Treatment for Exposure:
INHALATION: remove victim to fresh air; get medical attention. INGESTION. give large amounts
of water; do NOT induce vomiting. EYES: immediately wash with water for 15 min.; call physician.
SKIN. wash affected parts with water; treat as for hydrogen fluoride burn with iced benzalkonium
chloride soaks; Toxicity by Inhalation (Threshold Limit Value): Data not available; Short-Term
Inhalation Limits: Data not available; Toxicity by Ingestion: Data not available; Lute Toxicity: Data not
available; Vapor (Gas) Im'tm Characteristics: Data not available; Liquid or Solid Irritant
Characteristics: Data not available; Odor Threshold Data not available.
Fire Hazards - Flash Point : Not flammable; Flammable Limits in Air (96): Not flammable; Fire
Extinguishing Agents: Not pertinent; Fire Extinguishing Agents Not To Be Used: Not pertinent; Special
Hazards of Combustion Products: Irritating fumes of hydrogen fluoride may form in fires; Behavior
in Fire: Not pertinent; Ignition Temperature : Not pertinent; Electrical Hazard: Not pertinent; Burning