Laws of Science

Boyle's Law

In 1662, Robert Boyle discovered Boyle's Law.

His law explains the relationship between pressure (p) and volume (v) if temperature and amount are held constant (k).

If the volume of a container is increased, the pressure decreases.

If the volume of a container is decreased, the pressure increases.

The mathematical form of Boyle's Law is PV = k, where P is pressure, V is volume and k is a constant.

Important Points

This is an inverse proportion. As one value goes up, the other goes down.
If the temperature and the amount remain the same, P times V must always equal k.
So, if P1 times V1 = k and P2 times V2 = k, THEN P1 times V1 = P2 times V2

For a fuller explanation and problems to solve of Boyle's Law, go to http://www.fordhamprep.com/gcurran/sho/sho/lessons/lesson73.htm.

Charles' Law

In 1802 Joseph Louis Gay-Lussac discovered what became known as Charles' Law. It was called this because of Gay-Lussac's reference to Jacques Charles' work

This law explains the relationship between volume (v) and temperature (t) if pressure and amount are held constant (k).

If the volume of a container is increased, the temperature increases.

If the volume of a container is decreased, the temperature decreases.

The mathematical form of Charles' Law is V/T = k.

Important Points

This is a direct proportion.
If the pressure and amount remain constant, the volume-temperature fraction will always be the same. Volume divided by temperature must always equal k.
So, if V1 divided by T1 = k and V2 divided by T2 = k, THEN V1 divided by T1 = V2 divided by T2.
Every temperature used in a calculation must be in Kelvin, not Celsius degrees.

For a fuller explanation and to see examples of Charles' Law, go to http://www.fordhamprep.com/gcurran/sho/sho/lessons/lesson75.htm.