Chemical reactions occur when elements or compounds combine and create new compounds. Elements are substances that contain only one type of atom and are represented by unique symbols on the periodic ...

There are lots of different substances but only just over a hundred elements. An element is a substance that is made up of only one kind of atom. The atoms in a particular element are the same as each ...

Vol. 73, No. 5, Proceedings of the 2004 Biennial Meeting of The Philosophy of Science AssociationPart II: Symposia PapersEdited by Miriam Solomon (December 2006), pp. 864-875 (12 pages) In this ...

Everything we can see and touch, and quite a lot that we can’t as well, is made of tiny particles called atoms. Some substances, like particles of this iron, contain only one kind of atom. Iron is an ...

TimesMachine is an exclusive benefit for home delivery and digital subscribers. About the Archive This is a digitized version of an article from The Times’s print archive, before the start of online ...