when do we say that a solution is unsaturated
Saturated and unsaturated compounds In organic chemistry, a saturated compound is a chemical compound that has a chain of carbon atoms linked together by single bonds.[1] Alkanes are saturated hydrocarbons. An unsaturated compound is a chemical compound that contains carbon-carbon double bonds or triple bonds, such as those found in alkenes or alkynes, respectively. Saturated and unsaturated compounds need not consist only of a carbon atom chain. They can form straight chain, branched chain, or ring arrangements. They can have functional groups, as well. It is in this sense that fatty acids are classified as saturated or unsaturated. The amount of unsaturation of a fatty acid can be determined by finding its iodine number.
Partial pressure The form of the equilibrium constant shows that the concentration of a solute gas in a solution is directly proportional to the partial pressure of that gas above the solution. This statement is known as Henry's law and the equilibrium constant   k  {\displaystyle k}  is quite often referred to as the Henry's law constant.[8][9][10]