Henry’s law is a gas law which states that at the amount of gas that is dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid when the temperature is kept constant. The constant of proportionality for this relationship is called Henry’s law constant (usually denoted by ‘kH‘). The mathematical formula of Henry’s law is given by:
P ∝ C (or) P = kH.C
0r X = kH.P
- ‘P’ denotes the partial pressure of the gas in the atmosphere above the liquid.
- ‘C’ denotes the concentration of the dissolved gas.
- ‘kH’ is Henry’s law constant of the gas.
- X is a mole fraction of gas.
- Henry’s law in Carbonated soft drinks – When soft drinks bottle is opened some of the gas escapes giving a specific pop. this is due to the lower pressure above the liquid and carbon dioxide comes out as bubbles.
- Henry’s law in Respiration – The amount of oxygen that dissolves in the bloodstream is directly proportional to the partial pressure of oxygen in the alveoli air.