Unit+5+-+Combined+Gas+Law

To understand the Combined Gas Law, we must first know the three main laws that make it up:

Charles Law - //At constant pressure, the volume of a given mass of an ideal gas increases or decreases by the same factor as its temperature (in Kelvin) increases or decreases.//
 * Equation for Charles Law: V1/T1 = V2/T2**

Gay Lussac's Law - //The ratio between the combining volumes of gases and their reaction product, if gaseous, can be expressed in small whole numbers.//
 * Equation for the Gay law: P1/T1 = P2/T2**

Boyles Law - describes the relationship between the product pressure and volume within a closed system as constant when temperature and moles remain at a fixed measure
 * Equation for Boyle's Law = P1V1 = P2V2**

These three laws combine to create the combined gas law: P1V1/T1 = P2V2/T2


 * Example:**

A gas occupies a volume of 20 L (V1) at a pressure of 5 atm (P1) and a temperature of 500K (T1). What will the volume (V2) be if both the pressure is raised to 10 atm (P2) and temperature is changed to 250K (T2)? We first take our knowns: V1 = 20L P1 = 5 atm T1 = 500K V2 = ? P2 = 10 atm T2 = 250K Use the combined gas law formula and put in your knowns: P1 V1 / T1 = P2 V2 / T2 (5 atm ) (20 liter) / 500K = (10 atm) ( V2) / 250K Solving for V2 (5 atm) (20 L) (250 K) / ( 10 atm) (500 K) = V2 = 5 L.

See: http://www.chempractice.com/ for examples and quizzes for all the units.

See: http://www.youtube.com/watch?v=p0lCstWZWrI for a brief Combined Gas Law experiment.

See: http://www.youtube.com/watch?v=lUNSvDamzsw to watch some dude do a Combined Gas Law equation.