Chemistry

Bond energy — definition, measurement, and applications Bond energy Bond energy: the average gas‑phase bond dissociation energy for like bonds in a species. Key concept in thermochemistry, kinetics, materials design and computational chemistry.

Borax (sodium borate): properties, history, uses and safety Borax Borax, commonly called sodium borate, is a white crystalline mineral used in cleaning, glassmaking, agriculture and industry. This article summarizes its chemistry, occurrence, his…

Boric acid (H3BO3): properties, uses, and safety Boric acid Boric acid (H3BO3) is a boron-containing weak acid used in antiseptics, preservatives, insecticides, flame retardants and as a neutron absorber; it is toxic and regulated for repro…

Boron: properties, occurrence, compounds, uses, and biological role Boron Boron (B, atomic number 5) is a metalloid found in compounds like borax. This article covers its physical and chemical properties, allotropes, production, major uses, biological im…

Boron carbide (B4C) Boron carbide Boron carbide is an extremely hard, lightweight ceramic (B4C) used for abrasives, armor, neutron control, and wear-resistant components; it combines high hardness with chemical sta…

Boron group (Group 13) Boron group Group 13 of the periodic table — boron, aluminium, gallium, indium, thallium and nihonium — a family with three valence electrons, varied bonding, important industrial uses and not…

Brass: composition, properties, uses and history Brass Brass is a copper–zinc alloy valued for its appearance, workability and corrosion resistance. This article surveys its composition, microstructures, history, common types, uses, an…

Brine: saltwater solutions, properties, uses and distinctions Brine Brine is a concentrated salt solution of water and salts. This article explains its definition, chemistry, common uses (food, industry, de-icing, therapy), and how it differs from…

Bromate (BrO3−): Chemistry, Production, Uses, and Health Concerns Bromate Bromate is the oxyanion BrO3− (bromine in +5 oxidation state). A strong oxidant formed from bromide by ozone, electrolysis or chemical reactions; it occurs in industry and drinking…

Bromic acid (HBrO3): properties, preparation and related compounds Bromic acid Bromic acid (HBrO3) is the oxoacid of bromine in oxidation state +5. It exists mainly in aqueous solution, is a strong oxidizing agent, and is closely linked to bromate salts.

Bromide (Br−): the ion, its salts, uses and meanings Bromide Bromide is the anionic, reduced form of bromine. This article explains its chemical nature, common salts, industrial and historical uses, safety and environmental notes, and the id…

Bromine: properties, occurrence, uses and safety Bromine Bromine (Br, atomic number 35) is a reddish-brown, diatomic halogen element used in flame retardants, disinfectants and chemical synthesis; it is reactive, corrosive and found main…

Bromine dioxide (BrO2) — properties, structure and reactivity Bromine dioxide Bromine dioxide (BrO2) is an unstable, oxidizing bromine oxide species. This article summarizes its structure, preparation, reactions, limited uses, hazards and how it differs from…

Bromine monochloride (BrCl): properties, uses, and safety Bromine monochloride Bromine monochloride (BrCl) is a diatomic interhalogen compound used as an oxidizing and halogenating reagent. Overview of structure, preparation, applications, and precautions.

Bromine pentafluoride (BrF5): properties, uses and safety Bromine pentafluoride Bromine pentafluoride (BrF5) is a powerful interhalogen fluorinating agent and oxidizer. It is highly reactive and corrosive, hydrolyzes in moist air, and requires extreme precauti…

Bromine trifluoride (BrF3) Bromine trifluoride An overview of bromine trifluoride, an interhalogen compound used as a powerful fluorinating agent and oxidizer; covers structure, properties, handling, uses and notable distinctio…

Bromite (BrO2−): properties, formation, and chemical behavior Bromite Bromite is the oxyanion BrO2− (bromine in oxidation state +3). It is transient and unstable, formed from bromous acid and prone to disproportionation to bromate and bromide.

Bromous acid (HBrO2): properties, reactions and related species Bromous acid Bromous acid (HBrO2) is a rarely isolated halogen oxoacid of bromine in oxidation state +3. It is unstable in pure form and mainly encountered as the bromite ion or in solution and…

Bronze: the Copper‑Tin Alloy — Composition, History, and Uses Bronze Bronze is a family of copper alloys, typically alloyed with tin, prized for strength, corrosion resistance and castability. This article summarizes composition, types, history, pro…

Brown asbestos (amosite, grunerite): properties, uses, and health risks Brown asbestos Brown asbestos, commonly called amosite or grunerite, is one of six asbestos minerals. This article explains its composition, common uses, health hazards, and how it differs from o…

Büchner flask A thick-walled glass flask with a side-arm for vacuum-assisted filtration; commonly paired with a Büchner funnel or used where reduced pressure is needed. Safety, setup, and common…

Büchner funnel A laboratory vacuum filtration funnel with a flat perforated plate used with filter paper and a side-arm flask to separate liquids and solids quickly; named after Ernst Büchner.

Buffer solution: definition, behavior, composition and applications Buffer solution A buffer solution is a water-based mixture that resists pH change. This article explains composition, mechanism, types, capacity, preparation and common uses in biology, industry a…

Bug spray: uses, types, active ingredients, and safety Bug spray Overview of bug spray (insecticides and repellents), common active ingredients, application methods, safety guidance, environmental effects, and differences between repellents and…

Bunsen burner: laboratory flame used for heating, sterilization and analysis Bunsen burner Simple laboratory burner that mixes gas and air to produce a controllable flame. Used for heating, sterilization, flame tests and combustion demonstrations; includes design, operat…

Burette: Laboratory Glassware for Precise Liquid Dispensing Burette A burette (also spelled buret) is a graduated laboratory tube with a stopcock used to dispense and measure variable, precise volumes of liquid—commonly used in titrations and volum…

Butane (C4H10): Properties, Isomers, Uses and Safety Butane Butane is a four‑carbon alkane (C4H10) used as fuel, a refrigerant and an aerosol propellant. This article covers its structure, production, common applications, storage and safety…

Butene (C4H8): structure, isomers, production and uses Butene Butene is a four‑carbon alkene (C4H8) with a carbon–carbon double bond; it has four isomers and serves as a feedstock for polymers, fuels and chemical intermediates.

C8H16: Overview, Isomers, Properties, and Uses C8H16 C8H16 is a hydrocarbon formula shared by many alkenes and cycloalkanes. This article explains its structure, common isomers, physical and chemical traits, production routes, uses,…

Cadmium (Cd) — properties, uses, and environmental impact Cadmium Cadmium is a soft, silvery metal (symbol Cd, atomic number 48) used in batteries, pigments, and semiconductors; it is toxic and tightly regulated, with most production as a zinc by…

Cadmium bromide (CdBr2) Cadmium bromide Cadmium bromide is an inorganic cadmium(II) salt used as a laboratory reagent and precursor to other cadmium compounds. It is a water-soluble, toxic crystalline solid with notable…

Cadmium chloride (CdCl2) Cadmium chloride Cadmium chloride (CdCl2) is a water-soluble cadmium salt used in synthesis and materials chemistry. It is hygroscopic and toxic; proper handling, storage and disposal are required…

Cadmium fluoride (CdF2) Cadmium fluoride Cadmium fluoride is an inorganic ionic solid composed of cadmium cations and fluoride anions. It is a colorless crystalline compound with a fluorite-type structure, used mainly in…

Cadmium iodide Cadmium iodide (CdI2) is an ionic crystalline compound with a layered structure. It is used as a reagent and precursor in inorganic and organic chemistry and is notable for its tox…

Cadmium nitrate (Cd(NO3)2) Cadmium nitrate Cadmium nitrate, Cd(NO3)2, is a water-soluble cadmium(II) salt used as a laboratory reagent and precursor to other cadmium compounds. It forms hydrates, is an oxidizing nitrate, an…

Cadmium oxide (CdO): properties, production, uses and safety Cadmium oxide Cadmium oxide (CdO) is an inorganic compound used in pigments, electronics and battery manufacture. It is a crystalline metal oxide with notable semiconducting behavior and signifi…

Cadmium sulfate (CdSO4): properties, uses, and safety Cadmium sulfate Cadmium sulfate (CdSO4) is an inorganic cadmium salt of sulfate. This article summarizes its composition, common forms, preparation, applications, and health and environmental conc…

Cadmium sulfide (CdS) Cadmium sulfide Cadmium sulfide (CdS) is a yellow inorganic semiconductor used as a pigment and in optoelectronics; it occurs naturally and requires careful handling due to cadmium toxicity.

Cadmium telluride (CdTe) Cadmium telluride Cadmium telluride (CdTe) is a binary semiconductor used in thin-film photovoltaics, radiation detectors and infrared optics; it has a direct band gap and strong optical absorption…

Caesium (Cs): properties, history, uses, and safety Caesium Caesium (Cs, atomic number 55) is a soft, highly reactive alkali metal used in atomic clocks and industry. This article covers its properties, occurrence, applications, handling, a…

Caesium-137 Caesium-137 is a radioactive fission product of caesium used in industry and research; it is notable for environmental contamination after reactor accidents and a ~30-year half-lif…

Calcium — properties, uses, and biological significance Calcium Calcium (Ca, atomic number 20) is an alkaline earth metal essential in geology, industry, and biology; important for bones, signaling, cement, and common as carbonate and oxide com…

Calcium bromate: properties, preparation, uses and safety Calcium bromate Calcium bromate (Ca(BrO3)2) is an ionic bromate salt and oxidizing agent. This article summarizes its composition, chemical behavior, preparation routes, common uses and important…

Calcium carbonate: occurrence, properties, uses, and testing Calcium carbonate Overview of calcium carbonate (CaCO3): its forms, natural occurrence, physical and chemical behavior, common uses in industry and medicine, and simple tests to identify it.

Calcium chloride: properties, production, uses and precautions Calcium chloride Calcium chloride (CaCl2) is a hygroscopic inorganic salt used for de‑icing, drying, refrigeration brines, and food processing. It exists in anhydrous and hydrated forms and dissolv…

Calcium hydroxide (slaked lime): properties, production and uses Calcium hydroxide Calcium hydroxide (Ca(OH)2), known as slaked lime or hydrated lime, is a white alkaline compound used in construction, water and wastewater treatment, agriculture, and some food pr…

Calcium nitrate (Norwegian saltpeter) Calcium nitrate Calcium nitrate, Ca(NO3)2, is a water‑soluble nitrate salt used mainly as a fertilizer and concrete admixture; it is deliquescent, an oxidizer, and supplies both calcium and nitrog…

Calcium nitride (Ca3N2): properties, preparation and uses Calcium nitride Calcium nitride (Ca3N2) is an ionic inorganic compound composed of calcium cations and nitride anions; it is formed by reaction of calcium with nitrogen and hydrolyses to give ammo…