Solubility of gas in liquids

•Examples of pharmaceutical solutions of gases include: HCl, ammonia water & effervescent preparations containing CO2 maintained in solution under pressure.

• The solubility of a gas in a liquid is the concentration of dissolved gas when it is in equilibrium with some of the pure gas above the solution.

• The solubility depends on the pressure, temperature, presence of salts & chemical reactions that sometimes the gas undergoes with the solvent