|In chemistry, matter is defined as anything that occupies space and has mass. Basically, it comes in three states, classified according to their molecular separation and arrangement. First are solids. Solids have tightly-packed and regularly arranged particles. It takes on a definite shape and volume. Examples of solids are stone, mirror and ball. Next are liquids. Liquids have particles that are not as tightly packed as solids but have enough molecular affinity to control its volume to the shape of its container. It takes on the shape of its container and also has the ability to flow. Examples are water, oil and juice. Lastly are gases. Gases are the extreme on particle packing. Gas particles are so loose with each other that they cannot have a shape and at times, not visible at all. Examples are air, carbon dioxide and oxygen. There is another state, scientifically accepted, in the form of ionized gas. Its characteristics differ from gas so much that it was considered as separate state called plasma.
Matter can undergo changes and relatively, these can be classified into two: physical and chemical. Physical changes on a matter are characterized by a change in shape, size or any extrinsic property. Chemical changes on a matter, on the other hand, can be observed to be any process wherein chemical composition changes. In simpler terms, physical change is cutting the dough and chemical change refers to baking the dough to make bread. When matter undergoes a phase change, it is a physical change. From solid to liquid, the process is called melting. Vice versa, it is called solidification. Matter can be classified into two groups: pure and composite substances. Pure substance is any matter that can be observed for a particular condition, to have one state. Pure substances are classified into two: elements and compounds. Composite substances or mixtures are substances that are physically combined to form another substance. Mixtures can be either homogeneous or heterogeneous.
Posted 2010-12-14 and updated on Dec 14, 2010 5:50am by crisd