States of matter

• according to KMT - kinetic molecular theory of matter , gas particle are considered to be very small, have negligible attractive force existing between gas particles , this attractive force is called intermolecular force.
• molecule is a group of two or more atoms held together by a chemical force.
• compression - gas molecules are very far away from one another .
• pressure - moving bodies exerts pressure , pressure is define as force exerted per unit area.
• definite volume - the forces of attraction between the molecules of a liquid hold them together and allow them to occupy a fixed space.
• surface tension - define as the force on the surface of a liquid that makes the surface areas as small as posibble.
• solid are nearly incompressible , rigid and compact beacuse strong attractive force hold the particles.
• nematic - the molecules lie in the same direction but their end are not alligned.
• cholesteric phase - similar to nematic in arrangement, however each layer is rotated in fixed angle with respect to the next layer.
• freeezing occurs when a liquid changes to a solid.
• deposition - occurs when a gas changes directly to solid.
• physical change - is a characteristic can be observed without changing the substance into another substance.
• Chemical change - the characteristic that can be observed when a substance udergoes a change in its composition.
• NASA - National Aeronautics and Space Administration.