A gas has a solubility in water at 0 degrees C of 3.6 g/L at a pressure of 1.0 atm. What pressure is needed to produce an aqueous solution containing 9.5 g/L of the same gas at 0 degrees C?
a) 2.6 atm
b) 2.0 atm
c) 2.3 atm
d) 2.8 atm