ABSTRACT
This chapter provides general background on the types of estimation methods that are available, and guidance on how to proceed into a series of property predictions for a chemical when starting "from scratch", with a knowledge of the chemical's structure. It provides an abbreviated list that would suffice for a preliminary evaluation for most organic chemicals. The chapter discusses the positive and negative features of fragment constant-based estimation methods. Other properties are of interest primarily because they may be used as an input in some equation to estimate a more pertinent property. A good example of this is the octanol-water partition coefficient; this property is widely used as an indicator of a chemical's tendency to partition from water into organic matter, soil adsorption coefficients, and bio-concentration factors for aquatic life. Similarly, the activity coefficient may be used to estimate water solubility and Henry's law constant.
