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 ...

All substances have properties. These describe how a substance looks and behaves. There are two types of properties: physical and chemical. Watch this video about how physical and chemical properties ...

Chemical Reactions: A chemical reaction is a process where the substances 8unbdergo a change in their chemical composition. The substances that enter the reaction are called reactants that are then ...

Columbus, Ohio (September 8, 2009) – Chemical Abstracts Service (CAS), a division of the American Chemical Society, announced that on September 7 it recorded the 50 millionth substance in CAS REGISTRY ...

Understanding the differences between physical and chemical changes is the basics in the study of chemistry. These two types of transformations describe how substances can change in terms of their ...

Chemical purity is the most important quality characteristic of a pharmaceutical substance. This article describes the latest scientific and technological advances to meet recent pharmacopoeial and ...