
Chemical compound | Definition, Examples, & Types | Britannica
Dec 16, 2025 · All the matter in the universe is composed of the atoms of more than 100 different chemical elements, which are found both in pure form and combined in chemical compounds.
Chemistry | Definition, Topics, Types, History, & Facts | Britannica
Dec 26, 2025 · Cooking, fermentation, glass making, and metallurgy are all chemical processes that date from the beginnings of civilization. Today, vinyl, Teflon, liquid crystals, semiconductors, and …
Chemical reaction | Definition, Equations, Examples, & Types - Britannica
Jan 13, 2026 · Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Periodic table | Definition, Elements, Names, Symbols, Groups, Charges ...
Dec 22, 2025 · Periodic table, in chemistry, is an organized array of all the chemical elements in order of increasing atomic number. When the elements are thus arranged, there is a recurring pattern in …
Nitric oxide | Uses, Facts, & Definition | Britannica
Dec 27, 2025 · Nitric oxide, colourless toxic gas that has important chemical signaling functions in animals and is a serious air pollutant.
Cellular respiration | Definition, Equation, Cycle, Process, Reactants ...
Jan 9, 2026 · Cellular respiration, the process by which organisms combine oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and …
Chemical equilibrium | Definition, Equation, & Facts | Britannica
Chemical equilibrium is the condition in the course of a reversible chemical reaction in which no net change in the amounts of reactants and products occurs. A reversible chemical reaction is one in …
Chemical industry | Overview, Importance, & History | Britannica
Dec 5, 2025 · Chemical industry, complex of processes, operations, and organizations engaged in the manufacture of chemicals and their derivatives. Raw materials include fossil fuels and inorganic …
Lipid | Definition, Structure, Examples, Functions, Types, & Facts ...
Jan 13, 2026 · This section describes the structure and physical and chemical properties of fatty acids. It also explains how living organisms obtain fatty acids, both from their diets and through metabolic …
Boron | Properties, Uses, & Facts | Britannica
Jan 9, 2026 · Boron, chemical element that is a semimetal essential to plant growth and of wide industrial application. Typical effects of long-term boron deficiency are stunted, misshapen growth; …