Colorimetric analysis: principles, equipment, and applications Colorimetric analysis Colorimetric analysis determines concentration by measuring color intensity after a reagent reacts with a sample. Used in clinical labs, environmental testing and industry, often a…
Combinatorial chemistry: principles, techniques and applications Combinatorial chemistry Combinatorial chemistry is a set of methods for rapidly creating and testing large libraries of related chemical compounds, widely used in drug discovery, materials science and che…
Combustion: principles, types, uses and environmental impact Combustion Combustion is the reaction of a fuel with an oxidant that releases heat and often light. This article summarizes chemistry, types, common applications, emissions, safety measures a…
C4 (Composite Compound 4): a plastic military explosive Composite Compound 4 C4 is a stable, moldable plastic explosive based on RDX. Widely used in military and demolition work, it requires a detonator to function and is formulated for safe handling and de…
Compound: meanings in chemistry, language, and other fields Compound Overview of the term “compound,” its principal senses in chemistry and linguistics, characteristic features, examples, and other common usages and distinctions.
Computational chemistry Study and modelling of molecules, materials and reactions using algorithms and computers to predict structures, energies, spectra and dynamics that complement laboratory work.
Concentrate (substance) — overview, methods, uses and distinctions Concentrate A concentrate is a product in which much of a solvent or diluent has been removed to reduce volume and weight. Common in food, chemicals and industrial processes; reconstitution re…
Concentration (chemistry): definitions, measures, and applications Concentration Concentration describes the amount of one substance mixed into another. This article explains common units, how concentration is changed, methods of measurement, and practical uses…
Condensation: the phase change of gas into liquid Condensation Condensation is the physical process by which a gas becomes a liquid on cooling or compression; it drives cloud formation, dew, and many industrial processes and releases latent he…
Condenser (apparatus) A laboratory condenser is a cooling device that converts vapour into liquid. This article explains designs, operation, common types, uses in distillation and reflux, and safety con…
Conical measure (laboratory and measuring vessel) Conical measure A conical measure is a cone‑shaped container used to hold, mix and roughly measure liquids in laboratories, pharmacies and kitchens. It offers convenience and pourability but less…
Conjugated system: structure, properties, and applications Conjugated system A conjugated system is an arrangement of connected p-orbitals and delocalized electrons across alternating bonds. This article explains structure, behaviour, examples, and practica…
Conrotatory and Disrotatory Modes in Electrocyclic Reactions Conrotatory and disrotatory Definitions and distinctions between conrotatory and disrotatory electrocyclic motions, orbital-symmetry basis, thermal vs photochemical behavior, examples, and synthetic significa…
Conservation of Mass Fundamental principle that mass is neither created nor destroyed in ordinary chemical processes; covers statement, history, examples, and its relation to energy and nuclear reactio…
Contrail (condensation trail) Contrail A contrail is a cloud-like streak of ice crystals formed from aircraft exhaust or pressure changes at flight altitudes; they vary in appearance, persistence, climate effects, and a…
Coordination complex A coordination complex is a central atom or ion (often a transition metal) bound to surrounding ligands by coordinate bonds; central to catalysis, materials, bioinorganic chemistry…
Coordination geometry in chemistry: shapes and factors affecting complexes Coordination geometry Coordination geometry describes how ligands or atoms are arranged around a central atom in a complex. It explains common shapes, factors that determine geometry, historical backgro…
Copernicium (Element 112) Copernicium Copernicium (Cn, atomic number 112) is a synthetic, very short-lived superheavy element named for Nicolaus Copernicus; its chemistry is shaped by strong relativistic effects and re…
Copper (Cu): properties, history, and common uses Copper Copper (Cu) is a reddish transition metal (atomic number 29) prized for conductivity, corrosion resistance and malleability. It has wide uses in wiring, plumbing, alloys, architect…
Copper(I) acetylide (Cu2C2): properties, structure, and safe handling Copper(I) acetylide Detailed overview of copper(I) acetylide (Cu2C2): composition, molecular structure, physical and chemical properties, hazards, and recommended safe handling and storage practices
Copper(I) bromide (cuprous bromide) Copper(I) bromide Copper(I) bromide (CuBr) is an inorganic compound of copper in the +1 oxidation state. It is a sparingly soluble, often pale solid used as a source of Cu(I) in synthesis and as a s…
Copper(I) chloride (cuprous chloride) Copper(I) chloride Copper(I) chloride, CuCl, is a low-solubility copper salt in which copper is in the +1 state. It is used as a source of Cu(I) in chemistry, has distinct reactions from Cu(II) salts…
Copper(I) iodide (CuI): properties, preparation, and uses Copper(I) iodide Copper(I) iodide (CuI) is an inorganic compound of Cu+ and I−. This article summarizes its structure, preparation, common applications in chemistry and materials, and safety consid…
Copper(I) oxide (cuprous oxide) Copper(I) oxide Copper(I) oxide (Cu2O) is a red to reddish-brown inorganic compound, a p-type semiconductor used historically as a pigment and today in catalysts, antifouling paints, and research…
Copper(II) bromide (CuBr2) Copper(II) bromide Inorganic copper salt CuBr2: properties, structure, preparation, laboratory and industrial uses, handling, and differences from copper(I) bromide.
Copper(II) carbonate Copper(II) carbonate (CuCO3) is an inorganic copper salt of the carbonate ion. It is notable for its green–blue color, limited stability in water, and relation to common copper car…
Copper(II) chloride (cupric chloride) Copper(II) chloride An overview of copper(II) chloride (CuCl2): properties, structure, preparation, common uses, safety considerations, and distinctions from other copper chlorides.
Copper(II) hydroxide (cupric hydroxide) Copper(II) hydroxide An overview of copper(II) hydroxide (Cu(OH)2): properties, structure, preparation, reactions, uses in agriculture and industry, and distinctions from related copper compounds.
Copper(II) nitrate (Cu(NO3)2) Copper(II) nitrate Copper(II) nitrate, Cu(NO3)2, is a soluble blue-green copper salt used as a laboratory reagent, precursor to copper oxides and catalysts, and an oxidizing chemical; it requires car…
Copper(II) oxide (cupric oxide): properties, uses, and distinctions Copper(II) oxide Copper(II) oxide (CuO) is a black inorganic compound of copper in the +2 oxidation state. This article summarizes its structure, properties, preparation, uses, reactions, and safet…
Copper(II) sulfate (CuSO4) Copper(II) sulfate Copper(II) sulfate is a blue inorganic salt (formula CuSO4), commonly encountered as the pentahydrate. It is used as a reagent, fungicide, teaching chemical and in metal processing…
Corrosion: Causes, Types, Prevention, and Significance Corrosion Corrosion is the chemical or electrochemical degradation of materials. This article explains mechanisms, common forms, influencing factors, prevention techniques, history, and dist…
Corrosive substance A corrosive substance chemically damages living tissue or materials on contact. This article explains properties, common examples, hazards, safe handling, uses, and how corrosives…
Covalent bond A covalent bond is a chemical link formed when atoms share one or more pairs of electrons; this article explains its nature, types, theoretical models, examples, and differences fr…
Covalent radius The covalent radius is an estimate of an atom’s size when it participates in a covalent bond, defined empirically as half the distance between nuclei of two identical bonded atoms…
Cracking (chemistry): breaking large hydrocarbons into smaller molecules Cracking (chemistry) Cracking is the thermal or catalytic cleavage of large organic molecules (typically hydrocarbons) into smaller, more useful molecules such as alkanes and alkenes used in fuels and…
Crimson: appearance, origin, and cultural uses Crimson Crimson is a deep, slightly bluish red historically produced from insect dyes. This article explains its appearance, historical sources, symbolic meanings, common uses and how it d…
Crocin: natural carotenoid pigment from saffron and gardenia Crocin Crocin is a water-soluble carotenoid pigment responsible for saffron's red-orange color, found in Crocus and Gardenia species. It has culinary, historical dye uses and is investiga…
Cross-conjugation (organic chemistry) Cross-conjugation Cross-conjugation is a branching form of π-conjugation in organic molecules where conjugation paths diverge, altering electronic delocalization, reactivity, and spectroscopic prope…
Crucible (laboratory and metallurgical vessel) Crucible A crucible is a heat-resistant container used to melt, calcine, or chemically treat substances at high temperatures in labs and industry.
Cryolite (Na3AlF6): mineral properties and role in aluminium production Cryolite Cryolite (Na3AlF6) is a rare fluoride mineral, historically mined in Greenland and now mainly synthesized. It serves as the principal flux in the Hall–Héroult aluminium smelting pr…
Crystal: solids with ordered atomic structure and their formation Crystal A crystal is a solid whose atoms or molecules form a repeating, three-dimensional pattern. This article explains how crystals form, common structures, examples, uses, and how they…
Crystal structure: arrangement, symmetry and influence on material properties Crystal structure An overview of crystal structure: how atoms, ions or molecules arrange in repeating patterns, the unit cell and symmetry, major crystal systems, determination methods, and why stru…
Crystallinity: structure, measurement, and effects on material properties Crystallinity Crystallinity describes how atoms or molecules are arranged in a solid. It governs mechanical, optical and transport properties; is measured by X‑ray and calorimetric methods; and…
Crystallization: formation, mechanisms, and practical significance Crystallization Crystallization is the process by which atoms or molecules arrange into an ordered solid. This article explains nucleation and growth, modes of crystallization, practical methods,…
Crystallography: the study of atomic order in solids Crystallography Crystallography investigates how atoms are arranged and repeated in three-dimensional solids, using diffraction and symmetry analysis to determine structures important to mineralog…
Cupronickel — properties, composition, uses, and history Cupronickel Cupronickel is a copper–nickel alloy known for its silver color and corrosion resistance. Commonly used for coinage, marine hardware, and heat exchangers, it balances strength and…
Curing (polymer chemistry) Curing (chemistry) Curing is the chemical process that creates crosslinks in polymers, turning soft or liquid formulations into solid, durable networks. Methods include heat, catalysts, moisture and…
