To increase the solubility of a gas at constant temperature from 22 g/L, at 2.1 atm, to 30 g/L, the pressure would have to be increased to what?

Question

Chemistry help please I am doing a review for class

Answer 1

Henry's Law states that the solubility of a gas in a liquid is directly proportional to the pressure of that gas above the solution.  Thus to increase solubility from 22 g/L to 30 g/L, represents a 1.36 x increase (30/22).  To achieve this, one would want to increase the pressure by the same factor.

 

1.36 x 2.1 atm = 2.85 atm = 2.9 atm (to 2 significant figures)

 

You could also arrive at the same answer using P1V1/n1 = P2V2/n2 assuming a volume of 1 L and using grams in place of moles for n:

(2.1 atm)(1 L)/22 g = (x atm)(1 L)/30 g

x atm = (2.1)(30)/22

x = 2.9 atm