The States of Matter

Matter can exist in three main different states : Solid, Liquid and Gas. A close look at the picture above shows: a glass that holds water. This shows a liquid. It also shows a block, which is a solid, and bubbles of air, a mixture of gases.

Matter can change its state depending on the temperature and the pressure. The temperature at which this conversion happens is specific for that particular substance. We know the classic example of Water. It can exist in all three states. Each state has a different name: Ice, Water, and Water vapor or Steam.

The Kinetic Particle Theory of Matter

Matter is made up of particles which could be atoms, molecules or Ions. These particles require energy for movement. The particles in a solid are in a lower energy state and can only vibrate about their mean fixed positions. As the particles gain more energy through heating, they move faster. They overcome forces of attraction and transition into the next state, the liquid state. The particles in a Liquid can move about each other and are further apart. But the forces of attraction are still strong enough to keep them in the container they are placed. This explains their fixed volumes. They can take up the shape of the container in which they are placed. Particles of a gas have so much energy. They can move away from each other. They occupy the entire volume of the container in which they are placed. There is also a lot of inter particular spacing.