20. Which one of the following gases has the lowest value of Henry’s law constant

a. N₂

b. He

c. H₂

d. CO₂

e. O₂

Ans. d

Explanation : As the solubility increases value of Henry’s law constant decreases. Since  CO₂   is  most soluble in water among the given set of gases. Therefore CO_{2 has the lowest value of Henry’s  law constant.}