A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is ...

Part of Chemistry (Single Science) The nature of substances and chemical reactions This diagram shows that one carbon atom and two oxygen atoms combine to make up the units of carbon dioxide. Its ...

Valency is the combining power of an element. Elements in the same group of the periodic table have the same valency. The valency of an element is related to how many electrons are in the outer shell.

A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) composed of atoms from more than one element held together by chemical bonds. A molecule ...