The concentration of CO2 in a soft drink bottled with a partial pressure of CO2 of 4.0 atm over the liquid at 25 °C is 1.2 x 10-1 M. The Henry's law constant for CO2 at this temperature is __________.
3.0 x 10-2 mol/L-atm
4.5 x 10-3 mol/L-atm
5.6 x 10-3 mol/L-atm
2.3 x 10-2 mol/L-atm
Answer: 3.0 x 10-2 mol/L-atm