Combined+Kosky

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Combined Gas Law
 * Combined Gas Law** expresses the relationship between pressure, volume, and temperature of a fixed amount of gas. It is expressed as pressure times volume divided by temperature ( in Kelvins) is k, or the constant.

The combined gas law was created because of one major part of experiments. More often, an experiment undergoes a change in temperature, pressure and volume. When this happens, all three valriables must be delt with. So, Boyle's, Charles, and Gay-Lussacs Laws were combined into this one equation.

PV/T=k (In the equation k constant and depends on the amount of gas.)

P1V1/T1 = P2V2/T2 (The subscripts in this equation indicates to different sets of conditions, and T represents Kelvin temperature. From this expression, any value can be calculated if the other five are known. Note that each of the gas laws can be obtained from the combined gas law when the proper variable is constant.)

So, a sample problem would look like this.

You have a container with a volume of 4ml and a temperature of 279 kelvins and a pressure of 5atms. What is the temperature of another container at a pressure of 6atms and a temperature of 300 kelvins? Set it up like so: (5atms x 4ml) / 279 kelvins = (6atms x ?) / 300 kelvins (5 atms x 4ml x 300 kelvins) / (279 kelvins x 6 atms) = **3.5 ml** ---> Equation for the combined gas law