Hydrofluoric acid
- Hydrogen fluoride solution
Hydrofluoric acid | |
| |
| Formula | HF |
| Structure | |
| Description | A colorless fuming mobile aqueous solution with a pungent odor. |
| Uses | Cleaning cast iron, copper, brass, removing efflorescence from brick & stone, or sand particle from metallic castings, working over too heavily weighted silks, frosting, etching glass and enamel, polishing crystal glass, decomp cellulose, enameling & galvanizing iron, incr porosity of ceramics in analytical work to determine silicon dioxide. |
| Registry Numbers and Inventories. | |
| CAS | 7664-39-3 |
| EC (EINECS/ELINCS) | 231-634-8 |
| EC Index Number | 009-003-00-1 |
| EC Class | Very toxic; Corrosive |
| RTECS | MW7875000 |
| RTECS class | Mutagen; Reproductive Effector; Human Data; Primary Irritant |
| UN (DOT) | 1790 |
| Merck | 12,4837 |
| Beilstein/Gmelin | 166 (G) |
| RCRA | U134 |
| EPA OPP | 45601 |
| Swiss Giftliste 1 | G-4551 |
| Canada DSL/NDSL | DSL |
| US TSCA | Listed |
| Austrailia AICS | Listed |
| New Zealand | Listed |
| Japan ENCS (MITI) | Listed |
| Korea ECL | Listed |
| Properties. | |
| Formula | FH |
| Formula mass | 20.00 |
| Melting point, °C | -83 |
| Boiling point, °C | 19.5 |
| Vapor pressure, mmHg | 760 (20 C) |
| Vapor density (air=1) | 0.714 |
| Critical temperature | 230.6 |
| Critical pressure | 74.8 |
| Density | 0.0061 g/cm3 (50 C) |
| Solubility in water | Miscible |
| Viscosity | 0.012571 cp (20 C) |
| pKa/pKb | 3.19 (pKa) |
| Heat of fusion | 3.9 kJ/mol |
| Heat of vaporization | 7.5 kJ/mol |
| Hazards and Protection. | |
| Storage | Protect against physical damage. Store at in well-ventilated area, separated from other storage. |
| Handling | Containers of this material may be hazardous when emptied. Since emptied containers retain product residues (vapor, liquid, and/or solid), all hazard precautions given in the data sheet must be observed. Addition to water releases heat which can result in violent boiling and spattering. Always add slowly and in small amounts. Never use hot water. Never add water to acids. Always add acids to water. |
| Protection | Wear appropriate protective gloves, clothing and goggles. |
| Respirators | Wear positive pressure self-contained breathing apparatus (SCBA). |
| Small spills/leaks | Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Use water spray to knock-down vapors. Neutralize spilled material with crushed limestone, soda ash, or lime. Vapor knockdown water is corrosive or toxic and should be diked for containment. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. Neutralize with agricultural lime (CaO), crushed limestone (CaCO3) or sodium bicarbonate (NaHCO3). Water spill: Neutralize with agricultural lime (CaO), crushed limestone (CaCO3), or sodium bicarbonate (NaHCO3). Add soda ash (Na2CO3). Adjust pH to neutral (pH=7). Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. |
| Stability | Stable. |
| Incompatibilities | Attacks glass and any other silica containing material May react with common metals (iron, steel) to generate flammable hydrogen gas if diluted below 65% with water Reacts exothermically with chemical bases (examples: amines, amides, inorganic hydroxides) Reacts with cyanide salts and compounds to release gaseous hydrogen cyanide Reacts explosively with cyanogen fluoride, methanesulfonic acid or glycerol mixed with nitric acid Reacts violently with arsenic trioxide, phosphorus pentachloride, acetic anhydride, alkali metals, ammonium hydroxide, chlorosulfonic acid, ethylenediamine, fluorine, potassium permanganate, oleum, propylene oxide, vinyl acetate, mercury(II) oxide. |
| Decomposition | When heated to decomposition it emits highly corrosive fumes of hydrogen fluoride. |
| Fire. | ||||
| Fire fighting | Use water on fires in which hydrofluoric acid is involved. | |||
| Fire potential | Nonflammable hydrogen may be generated in piping or containers. | |||
| Hazards | When heated, it emits highly corrosive fumes of fluorides. Its corrosive action on metals can result in formation of hydrogen in containers and piping to create fire hazard. Toxic and irritating vapors are generated when heated. Will attack glass, concrete, and certain metals, especially those containing silica, such as cast iron. Will attack natural rubber, leather, and many organic materials. May generate flammable hydrogen gas in contact with some metals. | |||
| Combustion products | Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. | |||
| NFPA | Health | 4 | ||
| Flammability | 0 | |||
| Reactivity | 1 | |||
| Health. | |
| Exposure limit(s) | OSHA PEL: TWA 3 ppm NIOSH REL: TWA 3 ppm (2.5 mg/m3) C 6 ppm (5 mg/m3) 15-minute NIOSH IDLH: 30 ppm |
| Poison_Class | 2 |
| Exposure effects | The toxological properties of this substance have not been fully investigated. |
| Ingestion | Swallowing this material may be harmful or fatal. Symptoms may include severe stomach and intestinal irritation (nausea, vomiting, diarrhea), abdominal pain, and vomiting of blood. Swallowing this material may cause burns and destroy tissue in the mouth, throat, and digestive tract. Low blood pressure and shock may occur as a result of severe tissue injury. |
| Inhalation | Dyspnea, bronchospasm (with abnormal pfts and hypoxia), chemical pneumonitis, pulmonary edema (can be hemorrhagic), tracheobronchitis, upper airway obstruction, chemical burns (larynx, trachea, bronchi) and ards may occur following inhalation. |
| Skin | Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. |
| Eyes | Can cause permanent eye injury. Symptoms include stinging, tearing, redness, and swelling of eyes. Can injure the cornea and cause blindness. |
First aid |
|
| Ingestion | Seek medical assistance. |
| Inhalation | Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Effects may be delayed. |
| Skin | Remove all exposed clothing and jewelry taking necessary precautions to prevent secondary exposure to health care providers. Irrigate exposed areas promptly with copious amounts of water for at least 30 minutes. Wash the skin, including hair and nails, vigorously; do repeated soap washings. Discard contaminated clothing. |
| Eyes | In case of contact with liquefied gas, thaw frosted parts with lukewarm water Immediately flush skin with running water for at least 20 minutes. |
| Transport. | ||
| UN number | 1790 | |
| Response guide | 127 | |
| Hazard class | 8 | |
| PRTC | T | |
| Packing Group | I; II | |
| USCG CHRIS Code | HFX | |
| USCG Compatatibility Group | 1 Non-oxidizing mineral acids | |
| Std. Transport # | 4930024 | |
| IMO Pollution Category | B | |