Technology: the production of goods and services that mankind considers useful.  Technology is not the same as science, though in today's society the two are closely linked.  Many of our products – our computers, our plastics, our medicines – are direct products of our knowledge of the behaviour of atoms and molecules.  However, it is not necessary to understand the science in order to make use of technology.  Long before the chemistry of steel was understood, mankind knew how to make a better sword.

Theory: a well tested (as opposed to a hypothesis which is less well tested) explanation for observed events. A theory must allow one to make predictions which can be tested by experiment. When the results of those experiments are as predicted, it lends support to the theory as a good explanation. If the results are not as predicted, they may lead to the eventual modification of the theory, or even its replacement.

Temperature: a measurement of the average kinetic energy of molecules. Most mathematical relationships used in chemistry require the temperature in Kelvins. To convert from °C to K use the relationship:

K = °C + 273.15

Thermodynamics: the study of energy changes, including but not limited to, chemical reactions.

Thermodynamic Data: standard heats of formation and standard molar entropies.

Triple Point: the single temperature at which all three states of matter –solid, liquid and gas – are simultaneously in equilibrium.