Author Posts

May 7, 2018 at 12:28 pm

Let us observe several examples of matter and find out how they differ. We may first classify them according to two general categories-homogeneous or heterogeneous. This classification is based on easily observable properties.so as not to get confused,try to rememenber the origin of each term. The term homogenous comes from homo ( the same) and henus (kind) the term hetero means different. You will need to recall what you learned in previous science courses. Phase describes the physical state of matter-solid,liquid, and gas. For example, ice,liquid water, and steam are three phases of the same substance. The phase of a substance is dependent on the existing temperature and pressure. For ewample, at room condition,sodium chloride (table salt ) is solid,water is liquid ,and carbon dioxide is gas.each phase has the appearance throughout.when all parts of a chemical system have the same appearance and properties, it is describe as hom0geneous.sodium chloride,water,and carbon dioxide are all pure substances.

May 7, 2018 at 12:44 pm

These are all homogeneous. Are there homogeneous mixtures? You will find out as you proceed in your study of matter. When some substances are mixed, the different phases may still be identified. Each distinct phase is homogeneous. A system is heterogeneous when it has nonuniform appearance and different phases can be recognized. This means when the system ir divided into several porti0ns, different portions will have different appearance and different c0mpositi0n.