Question

Categorize the following objects as solid, liquid or gas and write in the given table.
A piece of chalk, milk, hydrogen, nitrogen, a stone, water, kerosene, CNG, a pen, petrol, LPG, juice, table, oxygen, carbon dioxide, a box

Answer 1

• The three primary states of matter are the solid, liquid, and gaseous states.
• The particles (ions, atoms or molecules) are tightly packed together in the solid. The forces between the particles are intense in such a way that the particles can not move freely but can only vibrate. As a result, the solid has a stable, definite shape and a certain volume. Solids can only change their shape by force as if they were broken or cut.
• A liquid is an almost incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of the pressure. Volume is defined if temperature and pressure are constant. As the solid is heated past its melting point, it becomes liquid as the pressure becomes greater than the triple point of the material.
• In gas, the molecules have enough kinetic energy such that the impact of the intermolecular forces is small (or zero for the ideal gas) and the normal distance between the adjacent molecules is much greater than the molecular size. The gas has no definite shape or volume, but it occupies the entire container in which it is confined.
  

Solids	Liquids	Gases
Chalk Stone A pen Table A box	Milk Water Kerosene Petrol Oxygen Juice	Hydrogen Nitrogen Oxygen L.P.G Carbon dioxide