Charles’ Law describes the relationship between the change in volume and the temperature of a gas. For an ideal gas, the volume and temperature of a gas are directly proportional if the pressure and number of moles are constant. Thus, this explains why the volume increases as the temperature of the gas increases, regardless of their differing chemical properties.
Charles’ Gas Law is commonly written as:
V = k*T
V is the volume of the gas
k is a constant
T is the temperature of gas
For example, if the temperature of molecular oxygen halves, with pressure and number of moles remaining constant, the volume of this particular gas should also halve. This phenomenon should apply to all gases, as volume is directly proportional to temperature. So doubling the temperature of molecular hydrogen should also double its volume.
Charles’ Gas Law has been used in conjunction with Boyle’s Law and Gay-Lussac’s Law to form the Combined Gas Law, which has itself been combined with Avogadro’s Law to form the Ideal Gas Law. The Ideal Gas Law still considers the relationship between volume and temperature, but it also includes the new variables pressure and number of moles. Thus, understanding Charles’ Law is crucial to understanding how the volume and temperature are related; and by extension its function in the Ideal Gas Law.
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