describes the relationship of the solubility of a gas
in a liquid
and the partial pressure
of that gas when it is in equilibrium with the liquid. For an ideal gas, concentration
and partial pressure are directly proportional if the temperature
remains constant. Thus, this explains why more gas is dissolved in the liquid if its partial pressure is higher.
Henry’s Law is commonly written as:
P = k*C
p is the partial pressure of the solute in the gas above the solution
C is the concentration of the solute
k is a constant
CO2 can dissolve in water to form carbonated water. So for example, if the partial pressure of CO2 doubles, the amount of CO2 which dissolves in water will also double. Conversely, if the partial pressure of CO2 halves, then the amount which dissolves in water also halves.
Thus, understanding Henry’s Law is crucial for understanding the solubility of gases
in a variety of liquids. It can even be applied to everyday examples such as carbonated soft drinks, where CO2 is purposely trapped within a can/bottle to create a high partial pressure, causing more CO2 to dissolve. Opening the soft drink can/bottle will relieve the high partial pressure of CO2, leading to the amount of CO2 dissolved to decrease, and eventually rendering the soft drink flat.