Mercuric potassium cyanide

  • Potassium tetracyanomercurate(II)
  • Dipotassium tetrakis(cyano-C)mercurate(2-)
  • Dipotassium tetracyanomercurate
Formula
K2[Hg(CN)4]
Structure
Description
A colorless crystalline solid.
Uses
In manufacture of mirrors to prevent silver coating from yellowing, as reagent in testing for free acids.

Registry Numbers and Inventories.
CAS
591-89-9
EC (EINECS/ELINCS)
209-735-3
RTECS
TT6230000
RTECS class
Other
UN (DOT)
1626
Merck
12,7856
Beilstein/Gmelin
10949 (G)
RCRA
P030
Japan ENCS (MITI)
Listed

Properties.
Formula
C4HgK2N4
Formula mass
382.86
Density
2.42 g/cm3
Solubility in water
Soluble
Refractive index
1.451
Thermal expansion
0.000018/K

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Do not use water on material itself.
Stability
No data.
Incompatibilities
Incompatible with strong oxidizing agents.
Decomposition
When heated to decomposition it emits toxic fumes of nitrogen oxide(x), mercury, potassium oxide and cyanide.

Fire.
Fire fighting
Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use alcohol foam, dry chemical or carbon dioxide. Do not use water on material itself. If large quantities of combustibles are involved, use water in flooding quantities as spray and fog. Use water spray to knock-down vapors.
Fire potential
Moderate fire hazard, by chem reaction with heat, moisture, acid; emit hydrocyanic acid.
Hazards
Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.). Substance will react with water (some violently), releasing corrosive and/or toxic gases. Reaction with water may generate much heat which will increase the concentration of fumes in the air. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.
Combustion products
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.

Health.
Exposure limit(s)
NIOSH REL: C 0.1 mg/m3 [skin] OSHA PEL: C 0.1 mg/m3 10 mg/m3 (as Hg)
Exposure effects
Initially, headache, vertigo, and agitation occur, followed by combative behavior, coma, seizures, and death. Acute exposure - neurologic: tremor, confusion, loss of coordination, hyperreflexia, and lethargy may follow acute mercuric chloride ingestion. Chronic exposure can cause fatigue, headache, weakness, decreased concentration, anxiety, emotional lability, irritability and delirium. Mercuric chloride has been associated with spontaneous abortions in humans. It has been embryotoxic, fetotoxic, and teratogenic, and has affected the testes and sperm in rodents.
   Ingestion
See Inhalation.
   Inhalation
Tachypnea, hyperpnea, and dyspnea followed rapidly by respiratory depression are common. Pulmonary edema may occur.
   Skin
Papules, rashes, pruritus, and ulcerations may occur.
   Eyes
Burning sensation of mouth and throat, and equally red retinal arteries and veins are common.

First aid
 
   Ingestion
Emergency measures - in symptomatic patients advance life support including use of the cyanide antidote kit should be initiated as gastrointestinal decontamination is being prepared. Emesis: ipecac-induced vomiting is not recommended because of the potential for cns depression and seizures. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents. Consider after ingestion of a potentially life-threatening amount of poison if it can be performed soon after ingestion (generally within 1 hour). Oxygen - immediately begin therapy with 100% oxygen.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists. While cyanide can be absorbed through intact skin, most reported cases have involved whole-body immersion in cyanide solutions or large-area burns with molten cyanide solutions.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
1626
Response guide
Hazard class
6.1
Packing Group
I
 
Std. Transport #
4923254