Question

what are atoms and molecules i want a clear definition

Answer 1

An atom is defined as the basic unit of element which possesses the properties of the element. By basic, we mean that it is the building block of matter . It is the smallest particle of an element that can take part in a chemical reaction. Every atom consists of protons, neutrons and electrons. For example Carbon will consist of atoms which will show the properties of carbon only and not any other element.


A molecule on the other hand is a group of two or more atoms which chemically combine together to form a single species, whose properties are different from that of the combining elements. For example, 2 atoms of Hydrogen and one atom of oxygen combine to form one molecule of water.

Answer 2

Atoms are the elments, in pure form not any combined state.
molecules are combinations of atoms.
Eg. H is hydrogen atom, H2 is hydrogen molecule.
o is oxygen atom, o2 is oxygen molecule