Integrated SequencePhysics Chemistry Organic Biology

Web Resources



  click if a link is broken



Special points of emphasis

The Ideal Gas and Kinetic Theory

The States of Matter

It is very fruitful, in general, in the physical sciences to put physical formulas at play in your imagination. Imagine the system described undergoing the changes modeled by the formula. What does the formula tell you? For the Ideal Gas Law, it is helpful to imagine the behavior of the system composed of an ideal gas successively subjected to various constraints. What would happen if the system were compressed at constant temperature? The answer is Boyle's Law, the product of the pressure and volume remains constant. What happens with heating at constant pressure? As the temperature increases at constant pressure, Charles' Law describes the changes that occur, the volume increases.

Similar reasoning can also be applied to understand how the Ideal Gas Law implies the Combined Gas Law and Gay-Lussac's Law. It is also helpful, furthermore, to go beyond interpreting the laws as a consequence of manipulating equations. Boyle's Law, Charles' Law and Gay-Lussac's Law were all discovered prior to the Ideal Gas Law. Use what you know of kinetic theory to imagine the particle level of a model thermodynamic system (the molecular level) and try to imagine the transformations described by the laws. For a constant temperature compression, for example, as described by Boyle's Law, we know that the average kinetic energy per particle is constant, so the vigor of molecular motion is not changed between the initial and final state. What has changed? The system has been compressed. There is less volume, so the gas is more dense; i.e. if we were to test the pressure with a piston barometer, more collisions would occur upon its surface, and higher pressure would be registered.








The WikiPremed MCAT Course is a free comprehensive course in the undergraduate level general sciences. Undergraduate level physics, chemistry, organic chemistry and biology are presented by this course as a unified whole within a spiraling curriculum.

Please read our policies on privacy and shipping & returns.  Contact Us.
MCAT is a registered trademark of the Association of American Medical Colleges, which does not endorse the WikiPremed Course.


Creative Commons License
The work of WikiPremed is published under a Creative Commons Attribution Share Alike 3.0 License. There are elements of work here, such as a subset of the images in the archive from WikiPedia, that originated as GNU General Public License works, so take care to follow the unique stipulations of that license in printed reproductions. You can use the resources here for commercial or non-commercial purposes, but please give attribution and a link to the production credits and edit history of the resource. For the works here which began as my individual work, please attribute "John Wetzel, an author at wikipremed.com".