Charles+Kosky

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Charles' Law
 * Charle's law** states that the volume of a fixed mass of gas at constant pressure varies directly with the Kelvin temperature. So, as the temperature increases, the volume does as well.

This law can be seen with an expandible container, such as a balloon. At constant pressure, as the temperature increases, so does the volume of the balloon. On the other hand, when the temperature is dramaticaly dropped, the volume of hte balloon decreases noticibly. This occurs because at a higher temperature, the gas particles move faster and collide with the walls of the balloon more frequently and with more force. The volume of the balloon has to increase in order for the pressure to remain the same.

V=kT or V/T=k (The value of T is the Kelvin temperature, and k in a constant. The ratio V/T for any set of volume-temperature values always equals the same as k.)

V1/T1=V2/T2 (V1 and T1 represent the initial condition. V2 and T2 represent a different set of conditions. When three of the four values are known, you can use this equation to calculate the fourth value for a system at constant pressure.)

As with all equations involving temperature, you must remember to convert any celcius degrees into kelvin temperatures by adding 273.

So, a sample problem would look like this.

You have a container with a volume of 4ml and a temperature of 274 kelvins. What is the temperature of another container at the same pressure with a temperature of 285 kelvins? Set it up like so: 4ml / 274 kelvins = ? / 285 kelvins (4ml/ 274 kelvins) x 285 kelvins= **4.13 ml** This image shows on the right the volume of the container versus the temperature gague at the bottom. It also relates pressure to the whole picture.