Henry's Law Constant (Mol/L · Atm) for Oxygen Dissolving in Blood

Multiple Choice

Henry's law constant (mol/L · atm) for oxygen dissolving in blood is 3.74 *10^-2 mol/L · atm at body temperature, 37°C. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

A) 7.8 *10^-3 M
B) 3.5 *10^-3 M
C) 2.3 *10^-2 M
D) 1.3 *10^-2 M
E) 0.11 M