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What Is Chemistry

Chemistry can be defined as the science that deals with the materials of the universe and the changes that these materials undergo.
Chemusts are involved in activities as diverse as examining the fundamental particles of matter, looking for molecules in space, making new materials of all types, using bacteria to produce such chemicals as insulin, ans finding new metods for early detection of desease.
Chemistry is often called the central science-and with good reason. Most of the phenomena that occur in the world around us involve chemical changes-changes in which one or more substances become different substance. Here are some examples of chemical changes:

  • Wood burns in air, forming water, carbon dioxide, and other substances.
  • A plant grows by assembling simple substances into more complex substances.
  • The steel in a car rusts.
  • Eggs, flour, sugar, and baking poeder are mixed and baked to yield a cake.
  • The definition of the term chemistry is learned and stored in the brain.
  • Emissions from a power plant lead to the formation of acid rain.

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