The combined gas law is a gas law that combines Charles's law, Boyle's law, and Gay-Lussac's law. It relates the pressure, volume, and temperature of a gas, and can be used to predict the behavior of a gas when one of these variables is changed.

The combined gas law is expressed by the equation:

**P1V1 / T1 = P2V2 / T2**

Where:

P1 = initial pressure

V1 = initial volume

T1 = initial temperature (in Kelvin)

P2 = final pressure

V2 = final volume

T2 = final temperature (in Kelvin)

The combined gas law can be used to calculate the final pressure, volume, or temperature of a gas when one of these variables is changed, while the other two variables remain constant. It is especially useful for solving problems involving changes in gas conditions.

For example, if a gas has an initial pressure of 1 atm, an initial volume of 1 L, and an initial temperature of 273 K, and the pressure is changed to 2 atm while the volume is changed to 2 L, the combined gas law can be used to calculate the final temperature of the gas.

Using the combined gas law equation, we can solve for T2:

1 * 1 / 273 = 2 * 2 / T2

273 = 4 / T2

T2 = 4 / 273

T2 ≈ 0.0147 K

- Understand the individual gas laws: Charles's law, Boyle's law, and Gay-Lussac's law.
- Learn how to convert temperatures from Celsius to Kelvin, as the combined gas law requires temperatures to be in Kelvin.
- Practice using the combined gas law equation to solve for the unknown variable when the other variables are given.
- Understand the units of pressure (atm, mmHg, kPa) and volume (L) commonly used in gas law problems.
- Review and practice solving problems involving changes in gas conditions using the combined gas law.

By mastering the combined gas law, you will be able to understand and predict the behavior of gases under different conditions, and solve problems related to changes in gas properties.

.Physical Science

Energy - A. Energy is involved in all physical and chemical processes. It is conserved, and can be transformed from one form to another and into work. At the atomic and nuclear levels energy is not continuous but exists in discrete amounts. Energy and mass are related through Einstein's equation E=mc 2 . B. The properties of atomic nuclei are responsible for energy-related phenomena such as radioactivity, fission and fusion. C. Changes in entropy and energy that accompany chemical reactions influence reaction paths. Chemical reactions result in the release or absorption of energy. D. The theory of electromagnetism explains that electricity and magnetism are closely related. Electric charges are the source of electric fields. Moving charges generate magnetic fields. E. Waves are the propagation of a disturbance. They transport energy and momentum but do not transport matter.

Relate temperature to the average molecular kinetic energy.