Mercury (Hg) Mercury (Hg) CAS#7439-97-6
Physical Properties: Mercury exists as a silver-white liquid metal under ambient temperature conditions, featuring high density (13.534 g/cm³), a low melting point (-38.83°C), and superior electrical and thermal conductive capabilities.
Toxicity and Hazards: This substance is highly toxic and can be absorbed via inhalation, ingestion, or skin contact. Chronic exposure may lead to neurological impairment and kidney damage, with notable bioaccumulation potential in the environment.
Chemical Reactivity: Mercury forms amalgams with the majority of metals, excluding iron and platinum. It undergoes a reaction with sulfur to produce mercuric sulfide (HgS) and is soluble in oxidizing acids such as nitric acid.
Applications: Its uses encompass dental amalgam formulations, thermometers, barometers, electrical switches, fluorescent lighting, and the gold mining industry (specifically in the amalgamation process).
Handling and Storage: Mercury must be stored in shatterproof, hermetically sealed containers (e.g., steel flasks) in well-ventilated environments. In the event of spills, contaminated areas should be treated with sulfur powder for effective decontamination.
Mercury (CAS: 7439-97-6; EINECS: 231-106-7), commonly known as Quicksilver, is an elemental heavy metal that exists as a liquid at ambient temperature. It is typically extracted from cinnabar ore, with a molecular weight of 200.59 g/mol.
Project | Details |
Product Name | Mercury / Quicksilver |
CAS Number | 7439-97-6 |
EINECS Number | 231-106-7 |
Chemical Type | Heavy metal / Elemental mercury |
Physical Form | Silvery-white, shiny liquid metal |
Molecular Weight | 200.59 g/mol |
Density | 13.534 g/cm³ (at 25°C) |
Boiling Point | 356.73°C (at 101,325 Pa) |
Melting Point | -38.83°C (at 101,325 Pa) |
Physical & Chemical Properties
Physical Characteristics: Demonstrates good electrical conductivity (suitable for switches and relays) and high thermal conductivity, enabling uniform heat distribution. It exhibits high surface tension, leading to the formation of spherical droplets on most surfaces. A measurable vapor pressure at room temperature necessitates adequate ventilation to mitigate inhalation risks.
Chemical Traits: Readily forms alloys (amalgams) with gold, silver, tin, and other metals, while showing no reactivity with iron or platinum. It is chemically inert to water, most acids (excluding nitric acid and concentrated sulfuric acid), and alkalis under standard conditions. Additionally, it reacts with sulfur to form mercuric sulfide (HgS) and is soluble in oxidizing acids.
Main Application Fields
Small-Scale Gold Mining: Utilized to form amalgams with gold extracted from ore, facilitating the separation of gold from sediment. The amalgam is subsequently heated to evaporate mercury, yielding pure gold.
Chlor-Alkali Industry: Employed as a flowing cathode in mercury cell electrolysis for the production of chlorine and sodium hydroxide (caustic soda), though this application is gradually being phased out due to environmental concerns.
Measuring Instruments: Incorporated into thermometers, barometers, and manometers, leveraging its uniform thermal expansion and liquid properties to indicate temperature or pressure.
Electrical Components: Used in tilt switches, thermostats, and relays, attributed to its high electrical conductivity and non-wetting behavior with various contact materials.
Dental Materials: Serves as a core component in dental amalgam, alloying with silver, tin, and copper powders to form a durable, wear-resistant restorative material for tooth fillings.
Other Applications: Also finds use in mercury-vapor lamps, fluorescent lamps, certain batteries, and as a catalyst in specific chemical synthesis reactions.
Toxicity and Hazards
Mercury is highly toxic and can be absorbed through inhalation, ingestion, or skin contact. Chronic exposure may result in neurological impairment and kidney damage, with significant bioaccumulation potential in the environment. Its vapor pressure at room temperature increases inhalation risks, requiring strict control measures during handling.
Packaging and Storage
Packaging Specifications: Typically supplied in heavy-duty steel drums or iron flasks with capacities of 34.5 kg, 76 lb, or 100 lb. Inner containers are constructed from shatterproof, corrosion-resistant materials such as coated steel or specialized plastics, with all packaging complying with hazardous material transport regulations.
Storage Conditions: Should be stored in a cool, well-ventilated, locked area, away from heat sources, direct sunlight, and incompatible substances (e.g., strong acids, acetylene, ammonia, halogens). Storage areas must be equipped with secondary containment systems to prevent environmental release and furnished with mercury spill kits.
Shelf Life: When stored in unopened, hermetically sealed original containers under proper conditions, mercury has an indefinite shelf life as an elemental substance that does not degrade. Regular inspections for leakage or corrosion of containers are recommended.
