As mentioned in my previous post, the studies of gases are much related on Volume, Temperature and Pressure.
For Boyle's Law, it studies the relationship between Volume and Pressure of a gas.
Definition: The pressure of an ideal gas at constant temperature varies inversely with its volume.
By mathematical expression, it will be:
is for volume
is for pressure
When the pressure increase, the volume decrease;
When the pressure decrease, the volume increase.
If you squeeze a balloon, you increase the pressure, then you will see the balloon contracted.
If you let your balloon floats up to the sky, the air pressure decrease and your balloon will expand.
So, as the temperature is fixed, we will have:
where is the proportional constant
Some other notes:
For Boyle's Law, the mass of the gas must be fixed.
For Boyle's Law, the temperature is fixed.
Boyle's Law is only suitable when the gas we are dealing is an Ideal Gas.