Science Fair Project Encyclopedia
Chemical substance
A chemical substance is any material substance used in or obtained by a process in chemistry:
- A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions.
- A chemical element is a substance that cannot be divided or changed into different substances by ordinary chemical methods. The smallest particle of such an element is an atom, which consists of electrons centered around a nucleus of protons and neutrons.
- A molecule is the smallest particle of an element or compound that retains the characteristics of the element or compound.
- An ion is an atom or group of atoms with a net electric charge, having lost (cation) or gained (anion) an electron.
03-10-2013 05:06:04
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details