Three States of Matter

At any given conditions of temperature and pressure matter exists in one of the three states - solid, liquid and gas.

The different characteristics of the three states of matter depend upon the relative closeness of particles that make up the substance. In solid state, the particles are held close together in a regular pattern by strong inter-molecular forces. In liquid state, inter-molecular forces are weak as compared to solid state hence the particles are less tightly held and allow them to move away from each other. In the gaseous state, the molecules are farthest apart as compared to solid and liquid states and the inter-molecular forces are negligible so the particles move randomly.