What is Chemistry?
There are three major areas of science. Biology is the study of living things. Physics is the study of the forces and natural laws affecting matter. Chemistry is the study of the composition, properties, and transformations of matter. Together, these three areas make up our knowledge of how the universe around us works, from the behavior of the tiniest particles of matter to the immense scale of stars and galaxies.
With such broad definitions, these disciplines often overlap. For example, chemical changes are very important in cellular biology, and these same changes may generate electricity, one of the forces studied in physics. This web site will focus on chemistry, but we will include parts of the other sciences when needed to explain a topic, or as interesting facts relating chemistry to larger concepts.
Chemistry is very important in our lives. For example, every cell in our bodies is powered by a chemical reaction involving sugar, oxygen, water, and carbon dioxide. Plants use sunlight and water in a different reaction to produce the oxygen we need to breathe. On a more mundane level, the electricity to start our cars is provided by a reaction in a battery; the gasoline burning inside the car's engine, another reaction, allows it to run. We cook with microwave ovens, which use the chemical properties of water to heat our food quickly and easily. Finally, the power being used by your computer right now to view this page may be provided by a nuclear reaction, the burning of coal, natural gas, or oil, or even a chemical change triggered by solar radiation. Everywhere you look, chemistry surrounds us!
Example Problem 1
Identify whether each topic should be included in chemistry, physics, or biology.
A. Studying the behavior of fish
B. Finding how long it will take for a falling object to hit the ground
C. Discovering the composition of an unknown liquid
D. Researching the effects of acid rain on a forest
E. Investigating the generation of electricity by a battery and the magnetic forces involved
Well, two of these problems are trick questions! A should be classified under biology, B is a physics problem, and C is a chemistry matter. D and E are more complicated. While research into a forest is biological, the acid present also causes changes to matter in the trees themselves, which is an area of chemistry. Both are applicable to this problem. Likewise, physics and chemistry are often related. Generating power through a battery is chemistry at work, but the magnetic fields generated by electricity are part of the physics domain.