Hydrochloric acid

  • Muriatic acid
Formula
HCl
Structure
Description
An aqueous solution of HCl. Colorless, fuming liquid with a pungent odor.
Uses
In the production of chlorides, refining ore in the production of tin and tantalum, for the neutralization of basic systems, as laboratory reagent, hydrolyzing of starch and proteins in the preparation of various food products, pickling and cleaning of metal products, as catalyst and solvent in organic synthesis, for oil- and gas-well treatment, in removing scale from boilers and heat-exchange equipment, pharmaceutic aid (acidifier).

Registry Numbers and Inventories.
CAS
7647-01-0
EC (EINECS/ELINCS)
231-595-7
EC Index Number
017-002-00-2
EC Class
Toxic; Corrosive
R 23 35
S 1/2 9 26 36/37/38 45
RTECS
MW4025000
RTECS class
Tumorigen; Mutagen; Reproductive Effector; Human Data; Primary Irritant
UN (DOT)
1789
Merck
13,4801
Beilstein/Gmelin
318 (G)
EPA OPP
45901
Swiss Giftliste 1
G-5658
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
ClH
Formula mass
36.46
Melting point, °C
-74
Boiling point, °C
109
Vapor pressure, mmHg
190 (25 C)
Vapor density (air=1)
1.25
Odor Threshold Odor threshold 7.0 mg/m3
Critical temperature
51.4
Critical pressure
81.6
Density
1.18 g/cm3
Solubility in water
Miscible
Thermal expansion
0.003769/K
Heat of fusion
1.98 kJ/mol
Heat of vaporization
15.1 kJ/mol

Hazards and Protection.
Storage
Keep away from oxidizing agents, particularly nitric acid and chlorates. Safeguard containers against mechanical injury.
E D2A
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. Emergency eyewash fountains and safety showers should be available in the immediate vicinity of potential exposure. Do not puncture or incinerate containers.
Protection
Wear appropriate chemical protective clothing.
Respirators
Wear positive pressure self-contained breathing apparatus.
Small spills/leaks
Keep material out of water sources and sewers. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. Neutralize spilled material with crushed limestone, soda ash, or lime. Do not use water on material itself. 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.
Stability
Stable under ordinary conditions of use and storage. Containers may burst when heated.
Incompatibilities
Reacts rapidly and exothermically with bases of all kinds. Reacts exothermically with carbonates (and hydrogen carbonates to generate carbon dioxide Reacts with sulfides, carbides, borides, phosphides, many metals (including aluminum, zinc, calcium, magnesium, iron, tin and all of the alkali metals) to generate flammable hydrogen gas Reacts violently with acetic anhydride, 2-aminoethanol, ammonium hydroxide, calcium phosphide, chlorosulfonic acid, 1,1-difluoroethylene, ethylenediamine, ethyleneimine, oleum, perchloric acid, b-propiolactone, propylene oxide, silver perchlorate/carbon tetrachloride mixture, sodium hydroxide, uranium(IV) phosphide, vinyl acetate, calcium carbide, rubidium carbide, cesium acetylide, rubidium acetylide, magnesium boride, mercury(II) sulfate.
Decomposition
When heated to decomposition, emits toxic hydrogen chloride fumes and will react with water or steam to produce heat and toxic and corrosive fumes. Thermal oxidative decomposition produces toxic chlorine fumes and explosive hydrogen gas.

Fire.
Fire fighting
Wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode. Structural firefighter's protective clothing is ineffective for fires involving hydrochloric acid. Stay away from ends of tanks. Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn.) Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use water spray to knock-down vapors.
Fire potential
Extreme heat or contact with metals can release flammable hydrogen gas
Hazards
Vapors from liquefied gas are initially heavier than air and spread along ground. Containers may explode when heated. Ruptured cylinders may rocket.
Combustion products
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
Health
3
 
Flammability
0
 
 
Reactivity
1
 

Health.
Exposure limit(s)
TLV: 5 ppm; 7.5 mg/m3 (ceiling values) (ACGIH 1992-1993). OSHA PEL: C 5 ppm (7 mg/m3) NIOSH REL: C 5 ppm (7 mg/m3) NIOSH IDLH: 50 ppm
Poison_Class
4
Exposure effects
Long-term exposure to concentrated vapors may cause erosion of teeth. Long term exposures seldom occur due to the corrosive properties of the acid.
   Ingestion
Corrosive! Swallowing hydrochloric acid can cause immediate pain and burns of the mouth, throat, esophagus and gastrointestinal tract. May cause nausea, vomiting, and diarrhea. Swallowing may be fatal.
   Inhalation
Corrosive! Inhalation of vapors can cause coughing, choking, inflammation of the nose, throat, and upper respiratory tract, and in severe cases, pulmonary edema, circulatory failure, and death.
   Skin
Corrosive! Can cause redness, pain, and severe skin burns. Concentrated solutions cause deep ulcers and discolor skin.
   Eyes
Corrosive! Vapors are irritating and may cause damage to the eyes. Contact may cause severe burns and permanent eye damage.

First aid
 
   Ingestion
Have person drink water or milk; do NOT induce vomiting.
   Inhalation
Remove person to fresh air; keep him warm and quiet and get medical attention immediately; start artificial respiration if breathing stops.
   Skin
Remove and isolate contaminated clothing and shoes. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number
1789
Response guide
Hazard class
8
Packing Group
II; III
 
USCG CHRIS Code
HDC
 
1 Non-oxidizing mineral acids
Std. Transport #
4920504
 
IMO Chemical Code
17
IMO Pollution Category
D
IMO Hazard code
S