Chemistry

Chemistry is the study of Electrons, Atoms and Molecules and of the ways to change Molecules.

• Element <–> Atom
• Compound <–> Molecule

The words Element and Compound were used when we knew very little about the nature of matter. All we had was this idea that something could be composed of basic elements that are unbreakable, that could not be reduced to something else, and we could put elements together to make compounds.

We knew, or at least believed, that gold was one of these indivisible things–gold was an element.

Experiments with electrolysis showed us that water could be broken into two different gases, so we at least knew that water was a Compound. The two gases were eventually given the names Hydrogen and Oxygen.

The word “element” can be a problem because it doesn’t necessarily refer to an individual piece. As more and more were learned about the smallest possible thing that could contribute to an Element, the word “Atom” was used, and as we learned more about what happens when atoms combine, the word “Molecule” was used for the result.

Chemistry goes beyond the study of chemical reactions, Stoichiometry, and includes areas of study such as Thermodynamics, Kinetics, Spectroscopy, Symmetry. Thermodynamics is the study of the Equilibriums of Chemical Reactions and Kinectics is the study of how fast a reaction will proceed toward equilibrium under specified conditions such as Concentration(s), Temperature and Pressure. Spectroscopy is the use of light sources and detectors to determine (or at least guess) the identity of a molecule.

Symmetry is the study of the geometries of molecules. When we say Symmetry, we tend to think of a more advanced mini-course–possibly the hardest area an undergraduate Chemistry student will face–but the ideas of symmetry are also needed at the very beginning when you start thinking about molecules. This shows up, particularly, a few weeks into the study of Organic Chemistry, when you have a model kit and you start building Hydrocarbons.