MERCURIC THIOCYANATE Chemical Properties
- Melting point:165 °C (dec.)(lit.)
- Density 3.71 g/mL at 25 °C(lit.)
- Flash point:120 °C
- storage temp. Store at RT.
- form Powder
- color White to pale yellow
- Water Solubility Soluble in dilute hydrochloric acid, potassium cyanide and ammonia. Slightly soluble in alcohol and ether. Insoluble in water.
- Sensitive Hygroscopic
- Merck 14,5890
- BRN 3561344
- Stability:Stable. Incompatible with strong acids. May be light or moisture sensitive.
- CAS DataBase Reference592-85-8(CAS DataBase Reference)
- EPA Substance Registry SystemMercuric thiocyanate (592-85-8)
MERCURIC THIOCYANATE Usage And Synthesis
- Chemical PropertiesMercuric thiocyanate is an inorganic chemical substance. It is a stable solid at room temperature, and depending upon the purity, it appears as odourless white crystalline powder or grey. It is insoluble in water and denser than water and sinks in water. On decomposition, mercuric thiocyanate releases hazardous substances such as cyanide vapours, vapours of mercury, oxides of nitrogen (NO, NO2), and oxides of sulphur (SO2, SO3). Mercury thiocyanate has limited uses in chemical synthesis.
- Chemical PropertiesMercury thiocyanate is a white, odorless powder.
- UsesFor Pharaoh's serpents (fireworks); intensifier in photography.
- Air & Water ReactionsInsoluble in water.
- Reactivity ProfileMERCURIC THIOCYANATE decomposes into its elements at about 165°C. Burns readily in air to generate a coil of cohesive ash resembling a serpent (hence used in a firework: Pharaoh's serpents). Swells up to many times its original volume if heated [USCG, 1999]. Soluble in dilute hydrochloric acid [Merck]. Incompatible with strong oxidizing agents.
- HazardHighly toxic by ingestion, inhalation, and skin absorption.
- Health HazardMercuric thiocyanate causes severe eye and skin irritation with possible burns and causes digestive and respiratory tract irritation with possible burns. It may impair fertility, may cause harm to the unborn child, is harmful if inhaled, may cause allergic skin reaction, may cause kidney damage, may cause CNS effects, is light sensitive, and is a severe marine pollutant. Contact with acids liberates very toxic gas. The target organs include kidneys, CNS, reproductive system, eyes, and skin.
- Safety ProfileA poison by ingestion and intraperitoneal routes. Moderately toxic by skin contact. Thermally unstable and decomposition may be vigorous. When heated to decomposition it emits very toxic fumes of Hg, NOx, SOx, and CN-. See also MERCURY COMPOUNDS and CYANATES.
- Potential ExposureMercury thiocyanate is used in photography and fireworks.
- ShippingUN1646 Mercury thiocyanate, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
- Purification MethodsRecrystallise it from H2O, and it can give various crystal forms depending on conditions. Its solubility in H2O is 0.069% at 25o, but is more soluble at higher temperatures. It decomposes to Hg above 165o. Poisonous. [Mason & Forgeng J Phys Chem 35 1121 1931, Birckenbach & Kolb Chem Ber 68 919 1935.]
- IncompatibilitiesIncompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Mercury thiocyanate is sensitive to heat; expands to many times its original volume and then decomposes at freezing/melting point forming toxic fumes of sulfur oxides, mercury cyanide, and nitrogen oxides. Contact with acid or acid fumes causes release of toxic mercury and cyanide vapors. Incompatible with chlorine, reducing agents such as hydrides, sulfides
- Waste DisposalSmall amounts may be destroyed by alkaline hydrolysis. Admixture with alkali can be followed by soil burial. Larger quantities can be disposed of by incineration in admixture with acetone or xylene and using effluent gas scrubbing. Do not reuse empty container; proper disposal required.
MERCURIC THIOCYANATE Preparation Products And Raw materials
- Raw materialsAmmonium thiocyanate