Chapter Three

Matter, Properties, and Changes

Properties of Matter!

A substance is a matter that has a uniform and unchanging compositions. They are also known as pure substances. Physical properties can be observed without rehabilitating a substance's composition. Physical properties also describe pure substances. The ability of a substance to change into one or more things or to combine with something is known as a chemical property. Length, volume, and mass are all extensive properties. An extensive property is dependent upon the amount of substances there. Intensive properties are independent upon the amount of substance there. Density is an example of an intensive. Solids, Liquids, and Gases are all states of matter.

Heterogeneous & Homogeneous

Mixtures are combinations of two or more pure substances in which each pure substance retains its individual chemical properties. Mixtures are classified as heterogeneous and homogeneous. Homogeneous mixtures have constant compositions throughout, It will always have a single phase. Homogeneous are known as solutions. Heterogeneous mixtures are ones that do NOT blend smoothly throughout and in which the individual substances stay distinct.

Separating Mixtures.

Distillation and Filtration are the most used separation techniques.But there is also Crystallization and Chromatography. Heterogeneous mixtures made up of solids and liquids are easily separated by filtration. Filtration is a technique that uses a porous barrier to separate solids from liquids. Homogeneous mixtures are mainly separated by distillation and distillation is a technique that is based on differences in the boiling points of the substances involved.

Elements and Compounds

Elements are pure substances that can't be separated into simpler substances by chemical and physical means. Each element has its own unique chemical name and symbol. The symbol has 1, 2, or, 3 letters. The first letter is ALWAYS capitalized and the other letter or letters are always lowercase. A compound is a combination of 2 or more different elements that are chemically combined.

Law Of Definite Proportions & Law Of Multiple Proportions !

Law of definite proportions states that, regardless of the amount, a compound is always composed of the same elements in the same proportion by mass.

Law of multiple proportions state that when different compounds are formed by a combination of the same elements, different masses of one element combine with the same relative mass of the other element in a ratio of small whole numbers