ABSTRACT
Water chemistry is important because several factors about water to be treated and then distributed or returned to the environment are determined through simple chemical analysis. Probably the most important determination that the water practitioner makes about water is its hardness. Water and wastewater operators as well as many others are chemists, because they are working with chemical substances, and it is important for operators to know and understand how those substances react. Emulsions represent a special case of a suspension. Oil and other hydrocarbons derived from petroleum generally float on water with negligible solubility in water. Water dissolves polar substances better than non-polar substances. This makes sense when we consider that water is a polar substance. Polar substances such as mineral acids, bases, and salts are easily dissolved in water—while non-polar substances such as oils, fats, and many organic compounds do not dissolve easily in water.
