In Chapter 5 the role of chemistry in living systems continues covering the concepts of pH. Atoms usually occur in combinations within living systems, so the concepts of chemical bonding are explored. The chapter concludes with interactive activities that teach the basics of balancing chemical equations. This product uses the interactive capabilities of a computer. The chapter has embedded an end of chapter quiz, uses graphics, animations or user interactivity on almost all pages. This product is designed to provide bite-sized pieces of information in an effort to enhance the scientific literacy of our next generation, not to overwhelm them with sheer quantity of information. Chapter 5 sections: Acids, Bases and pH • Molecules • Chemical Equations • Checking Your Understanding. This product works both on a Macintosh or PC computer.