Question

what are the 5 main points of Dalton's atomic theory?

Answer 1

Elements are made of small particles called atoms.
All atoms of a given element are identical.
The atoms of a given element are different from those of any other element; the atoms of different elements can be distinguished from one another by their respective relative weights.
Atoms of one element can combine with atoms of other elements to form chemical compounds; a given compound always has the same relative numbers of types of atoms.
Atoms cannot be created, divided into smaller particles, nor destroyed in the chemical process; a chemical reaction simply changes the way atoms are grouped