
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.
Chemical Definition & Meaning | Britannica Dictionary
CHEMICAL meaning: 1 : of or relating to chemistry; 2 : working by means of chemicals
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.
Ethanol | Definition, Formula, Uses, & Facts | Britannica
Dec 3, 2025 · Ethanol is an important industrial chemical; it is used as a solvent, in the synthesis of other organic chemicals, and as an additive to gasoline. It is also the intoxicating ingredient of many …
Lead | Definition, Uses, Properties, & Facts | Britannica
Jan 7, 2026 · What is lead as a chemical element? What does lead look like and what is its symbol on the periodic table? Where is lead found in nature? What are some uses of lead in everyday life?
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 …