An Introduction To Chemistry

Chemistry (kem'is tree): noun. The science in which substances are examined to find out what they are made of, how they act under different conditions, and how they are combined or separated to/from other substances.¹

To paraphrase that, Chemistry deals with finding what different substances are made of, what kind of transformations take place, and different chemically related facts about a certain organism or substance.

Physical Chemistry is the study of the patterns of chemical behavior in chemical reactions under various conditions, which result from the chemical and physical properties of substances. Much of physical chemistry involves measurement of some kind. It covers the follwoing:

Solids, liquids and gases	Behavior of acids and bases
The physical and chemical composition of substances - their particles and bonding.	Solubility (how a substance dissolves)
The structure of the atom and its importance in the structure of substances.	Representations of chemical reactions (writing and balancing equations)
The measurement of quantities and the relationship between amounts of liquids, gases and solids.	Changes during chemical reactions: energy and chemical reactions rates of reaction oxidation reduction equalibrium
Electrolysis and reactivity	The different levels of reactivity shown by substances and the reason for this.

1: Webster's New World Dictionary: Basic School Edition, copyright © 1971 and 1961, 1966 by The World Publishing Company.