CHEMISTRY
Lecture 1: Introduction to Chemistry
A short original lesson introducing important chemistry terms.
What is chemistry?
Chemistry is the study of matter, its properties, composition and the changes it undergoes.
Atom and element
An atom is a basic unit of an element. An element is a pure substance made of one kind of atom.
Compound and mixture
A compound forms when elements are chemically combined in a fixed ratio. A mixture contains substances together without chemical combination.
Remember
Do not confuse a compound with a mixture: compounds have chemical bonding and fixed composition, while mixtures can have variable composition.