Question

State Henry’s Law and mention some important applications?

Answer 1

There is a relation between the gas dissolved in a liquid and the partial pressure of the gas present above the liquid. This relationship was formulated by William Henry.

Complete step by step solution:
-William Henry formulated a gas law which states that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid. The constant of proportionality is called the Henry’s law constant. The mathematical formula of Henry’s Law according to the definition is
$P\propto C$
$P={{k}_{H}}C$
Here, ${{k}_{H}}$is the constant of proportionality or the Henry’s Law constant.
P is the partial pressure of the gas above the liquid and C is the concentration of the gas which is dissolved in the same liquid.
-We can write the above equation in terms of mole fraction X.
$X={{k}_{H}}P$
-Now let us move on to the application of Henry’s Law.
-Henry’s Law has application in carbonated beverages. Carbonated beverages contain carbon dioxide in it. When pressure is increased the solubility of carbon dioxide increases. So, in a bottled carbonated drink, the carbon dioxide is dissolved in the liquid and it has very high pressure. When the bottle is opened, the atmospheric pressure is less than the pressure inside the bottle and so its solubility decreases and gas bubbles are released from the liquid.
-In respiration, Henry’s Law has an application. In bloodstream, the amount of oxygen dissolved is directly proportional to the partial pressure of oxygen present in the alveoli air.

Note: We should note that the solubility of gas in the liquid is directly proportional to partial pressure of the gas outside. It is not related to the partial pressure of the gas in the liquid.