Physics for Chemists |
This Web course is intended to cover the basic Physics that is needed for a University Chemistry course. You can select individual tutorials by clicking on the navigation bar on the left |
It has been claimed that Theoretical and Physical Chemistry is nothing more than applied physics. It could equally well be claimed that Physics is nothing more than Applied Mathematics (and if you have a taste for the absurd you could consider extending this chain ad nauseam, e.g. via philosophy, theology ...). The skill of the physical chemist is to be able to translate chemical problems into the language of applied physics and mathematics and to solve them.
It is a common refrain in Oxford, that if you want to do something, do it properly. Although this is always our aim, it is a bit of an overstatement. We need to take the pragmatic view that 'properly' means 'at a level appropriate to the result required'. Nobody in their right minds would insist that you read and understand Russell's "The Principles of Mathematics" before learning to add (although you probably don't really "understand properly" what a number is until you have studied the logical foundations of maths). Similarly to understand particle motion at the molecular level "properly" you need relativistic quantum mechanics, or even quantum electrodynamics, but at the level necessary to study most chemical phenomena this is pointless.
Physical chemists aim to find the most parsimonious and compact description we can get away with, to know its limitations, and to know where to go if these limitations are important. Sometimes you may spot the most insidious type of approximation, "implicit assumptions", which are so obvious that they are not questioned. Question them, or you will not understand the limits properly.
We therefore start with the simplest theories, and as we learn about new approaches, we understand the limits of these theories better. The simplest reasonable theories that can be applied to particles and their motion are those of classical mechanics, and to a great extent more detailed theories (quantum mechanics, relativistic mechanics, statistical mechanics) are based on these ideas. It is therefore absolutely vital to have a solid grounding in the basic concepts of classical physics.