This document discusses water and pH. It contains figures and tables about the structure of water molecules, hydrogen and hydroxide ions, and pH scales. Water is a polar covalent molecule with oxygen being slightly negative and hydrogens being slightly positive. The pH scale measures hydrogen ion concentration on a scale from 0 to 14, with 7 being neutral, below 7 being acidic, and above 7 being basic. Examples of common substances and their pH values are shown ranging from stomach acid to drain cleaner.