Boyle's Law

If you have ever squeezed a balloon, you have probably noticed that the confined gas can be compressed into a smaller volume.  In fact, this is known as Boyle's Law.  Robert Boyle discovered that doubling the pressure on a sample of gas at constant temperature reduces its volume by one-half. In other words, if one variable increases, the other decreases.
 
 

After performing many experiments with gases at constant temperature, Boyle had four major findings:

1-If the pressure of a gas increases, its volume decreases proportionally.
2-If the pressure of a gas decreases, its volume increases proportionally.
3-If the volume of a gas increases, its pressure decreases proportionally
4-If the volume of a gas decreases, tit pressure increases proportionally.
 

Let's take a closer look at the kinetic molecular theory to understand why pressure and volume is related in this way.  The pressure of a gas is caused by moving molecules hitting the container walls.  Suppose the volume of a container is decreased but the same number of gas molecules. is present at the same temperature.  As there will be more molecules per unit volume.  Therefore, the number of collisions with a given unit of wall area will increase as a result.  In addition, the pressure will also increase.

A phenomena that is a result of Boyle's Law is the famous Cartesian Diver.  To take a look at this phenomena, click below:

The Cartesian Diver


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