Classification

                   States of matter

            Matter is a material substance that occupies space, has mass and is composed predominantly of atoms consisting of protons, nuetrons and electrons that constitutes the observable universe, and that is interconvertible with energy. A sample of matter can be gas, a liquid, or a solid. These three forms of matter are called the states of matter. These states of matter are classified to its volume or shape.
             A gas or also known as vapor has no fixed volume or shape. It conforms to the volume and shape of its container. A gas can be compressed to occupy a smaller volume, or it can expand to occupy a larger one.
             A liquid has a distinct volume independent of its container, but it has no specific shape. It assumes the shape of a portion of the container that it contains.
             A solid has both a definite shape and a definite volume. In addition, solid is rigid.