Category: Microscopic World

  • Derivation of Average Speed of Gaseous Molecules

    We can start by analyzing equation #15 from the Derivation of Ideal Gas Law below: Because we want to derive the equation to the speed of gaseous molecules, the most important factor come to mind is the speed vx. Therefore, the equation will be 1. Canceling out from both side we get: 2. Since R = Nak. …

  • Derivation of PV=nRT, The Equation of Ideal Gas

    According to the kinetic theory of gas, – Gases are composed of very small molecules and their number of molecules is very large. – These molecules are elastic. – They are negligible size compare to their container. – Their thermal motions are random. To begin, let’s visualize a rectangular box with length L, areas of…

  • Motion of Molecules

    The idea that molecules are in constant motion was proposed by the kinentic theory of gases. The development of this theory in the 19th century are mostly based on the theory of atoms & molecules. Since there are no real experiments during that time, many leading physicists strongly opposed the idea. However, Brownian Motion, an observation done…

  • Concept of the Molecule

    Although the atomic theory proposed by John Dalton created a basic structure of the atom, the general idea of molecules was not cleared. In 1809, Frech chemist Joseph-Louis Gay-Lussac and others began doing numerous experiments with gases by measuring the amounts of gass that actually reacted. They found that two volumes of hydrogen reacted with…

  • Atomic Proposal

    The Idea of the atom were first proposed by the Greek philosophers Democritus and Leucippus around 400 B.C. At that time, there is absolutely no real evidence that support this proposal. Even after 20 centuries later, no experiment was strong enough to verify the existence of the atom.  In the 18th Century, the first scientific data on…