Nov 11, 2025 · Chemical compound, any substance composed of identical molecules consisting of atoms of two or more chemical elements. All the matter in the universe is composed of the atoms of …

Compounds can be broken down into their constituents to various degrees or changed into new compounds by chemical reactions. Atoms always combine into molecules in fixed proportions, …

Nov 11, 2025 · Chemical compound - Elements, Molecules, Reactions: Chemical compounds may be classified according to several different criteria. One common method is based on the specific …

Oct 18, 2025 · Broader definitions of a base, to include substances that exhibit typical basic behaviour as pure compounds or when dissolved in solvents other than water, are given by the Brønsted-Lowry …

A substance made of such molecules is called a chemical compound. Water is a chemical compound because its molecules have two hydrogen atoms and one oxygen atom.

Dec 2, 2025 · Caffeine, nitrogenous organic compound of the alkaloid group, substances that have marked physiological effects. Caffeine occurs in tea, coffee, guarana, maté, kola nuts, and cacao.

Nov 5, 2025 · Sugar, any of numerous sweet, colorless, water-soluble compounds present in the sap of seed plants and the milk of mammals and making up the simplest group of carbohydrates. The most …

Nov 29, 2025 · Linear compounds such as cellulose often pack together to form a rigid structure; branched forms (e.g., gum arabic) generally are soluble in water and make pastes.

Oct 17, 2025 · Calcium carbonate (CaCO3), chemical compound consisting of one atom of calcium, one of carbon, and three of oxygen that is the major constituent of limestone, marble, chalk, eggshells, …

Oct 23, 2025 · While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any …