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THE MADAM C. J. WALKER SCHOOLS Chemistry may be defined as the science that deals with the composition of substances and the laws governing the relation of their component parts. MATTER is anything that occupies space, that has weight and that is detectable by the senses. STATES OF MATTER - 1. Solid - Anything whose particles cling so close together as to resist changing its shape. 2. Liquid - Anything whose particles move freely, yet cling together and take the shape of its containing vessel. 3. Gas - Anything in an aeriform state (like hair) which tends to expand indefinitely. ATOM: This is the smallest particle of matter that exists. MOLECULE: The smallest group of atoms which can exist and retain the properties and character of the mass from which it is separated. If a molecule is divided it breaks up into particles with properties that are different from the original mass from which it was taken. Such divisions no longer remain molecules but then become atoms. Atoms and molecules are far too small to be visible to the human eye or even by the strongest microscope. It has been only by long and diligent research that their presence and something about their actions have been discovered. Matter, in what ever state it may exist, is composed of a multiplicity of molecules which are supposedly in constant motion. This molecular motion is actuated by some mysterious force about which science knows but little except that it differs in the various forms of matter and that it is one of life's deep secrets. It is supposed that these tiny molecules are attracted to each other by the energy possessed by each individual molecule and that in the three forms of matter it varies. In solids the molecules are very close together, held so by some great cohesive force. In liquids the molecules are not so close together, there being less of the mysterious attracting force. In gases the molecules are least close together, there being little mutual attraction. ELEMENT: An element is a substance which can not be decomposed or separated into simpler substances by any known method. The component parts of an element, that is to say, the atoms are all alike. Hydrogen, Oxygen, Nitrogen, Carbon, Chlorine, Magnesium, Silicon, Calcium, Sulphur, Iodine and Phosphorus are some of the common elements important to us as beauticians 122 TEXT BOOK OF BEAUTY CULTURE because they, along with a few others, are found in the human body. Gold, silver, iron, zinc and mercury are common metallic elements. COMPOUND: This is a substance obtained by mixing two or more different elements or ingredients in definite proportions. Substances can undergo two kinds of change, physical and chemical. Physical Change - This is a change in the property or form of a substance without changing its composition. Freezing water to make ice, boiling water to make steam, and magnetizing iron are examples of physical change. Chemical Change - Changing the composition of matter, and by so doing creating new substances with new properties is known as chemical change. For instance, common salt, referred to heretofore as a common, harmless compound, can be changed in a laboratory into sodium chloride and into chlorine, each separate substances possessing characteristics different from salt from which they were derived. Water, through chemical analysis, may be separated into Hydrogen and Oxygen, its component parts. Such changes are known as chemical changes. Solution - As a general rule, for any given substance there can be found some other substance in which it will dissolve or change its properties. The combination of these dissolved substances is then called solution. Solute - The substance dissolved is called a solute. Solvent - The substance in which the dissolving takes place is called a solvent. The common solvents we beauticians need know about are water, alcohol, glycerin and ether. KINDS OF SOLUTIONS: Simple - A solution containing a small portion of a solute. Compound - A solution containing two or more solutes. Concentrated - A solution containing a large portion of a solute. Saturated - A solution with water as the solvent. Tincture - A solution in which alcohol is the solvent. Glycerated - A solution in which glycerin is the solvent. Etherized - A solution in which either is the solvent. The combining or building up of new substances from chemical 123
