Matter

Particulate Nature of Matter

Matter is anything that occupies space and has mass.

The particle theory of matter states that matter is made up of a large number of tiny and discrete particles.

Atoms, Molecules, Ions

Atom:
The atom is the smallest, indivisible particle of an element. Atoms of the same element are exactly alike and are different from the atoms of all other elements.

Molecule:
Molecules are the smallest particles of an element or compound that are made up of two or more atoms.

Ions:
Ions are particles that are charged due to loss or gain of electrons.
Ions which are positively charged are called cations. Ions which are negatively charged are called anions.

Kinetic Theory of Matter

1. The gas consists of very small particles, each of which has a mass.
2. These molecules are in constant, random motion. The rapidly moving particles constantly collide with each other and with the walls of the container.
3. There are forces of attraction between particles of matter. These attraction forces will increase as the distance between the particles becomes closer.
4. The average kinetic energy of the gas particles depends only on the temperature of the system. The higher the temperature, the higher the kinetic energy of the particles.

Element and Compound

Element:
Chemical element is the class of atoms with the same number of protons in the nucleus. An element consists of only one type of atom. Element can be either atoms or molecules.

Compound:
A compound is any substance composed of identical molecules consisting of atoms of two or more elements. A compound is made up of either molecules or ions.

Prove of particulate nature of matter.

1. Diffusion
2. Brownian motion