STRUCTURE OF THE ATOM

Atom is smallest particle of an element that has all the chemical properties of that element.
The first philosopher to consider the idea that matter is made up of particles who was a Democritus.
 About 2000 years later an Englishman called John Dalton provided experimental evidence to convince people that matter is made up of particles called atoms

DALTON ATOMIC THEORY
Dalton atomic theory summarised below

1. matter is made up of tiny particles called atoms.
2. Atoms cannot be created or destroyed
3. The atoms of any one element are identical and have the same chemical properties and the same mass.
4. The atoms of a given element are different from those of any other element.
5. atoms of one element can combine with atoms of another element in simple combination ratio

MODIFICATION OF DALTON ATOMIC THEORY
Modern scientists modifiedDalton atomic theory as follows;

1. Atoms can be created or destroyed by means of nuclear reactions.
2. The same atoms can have different atomic mass this element are called isotopes
3. An atom is made up of more smaller subatomic particles called subatomic called the protons, neutrons and electrons.
4. atoms of different elements combine in many ratios toform complex compounds