Sep 26, 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.

Sep 23, 2025 · The identification of pure substances and the analysis of chemical mixtures enable all other chemical disciplines to flourish. The importance of analytical chemistry has never …

Chemical compounds of gold include potassium dicyanoaurate, K [Au (CN) 2], used in gold electroplating baths, and chloroauric acid, HAuCl 4, used as an intermediate in the production …

Oct 10, 2025 · A chemical reaction is a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either …

Sep 25, 2025 · The effects of biotin deficiencies in rats. Left, a rat fed on a biotin-deficient diet. Right, the same rat after three months on a diet with an adequate amount of biotin. (more) …

People have invented ways to use the chemical energy of substances to power machines. For example, the chemical energy inside the substances in a battery can be transformed into …

Jan 11, 1971 · The Chemical Brothers, a British deejay-producer duo who pioneered the big beat dance music genre in the 1990s with such singles as ‘Chemical Beats,’ ‘Block Rockin’ Beats,’ …

Hydroxide, any chemical compound containing one or more groups, each comprising one atom each of oxygen and hydrogen bonded together and functioning as the negatively charged ion …

Oct 13, 2025 · A polymer is any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, which are multiples of simpler chemical units called …

Sep 20, 2025 · Chemical formula, any of several kinds of expressions of the composition or structure of chemical compounds. The forms commonly encountered are empirical, molecular, …