CO2 diffuses more easily through the respiratory membrane than O2 because it is: (A) Less dense, (B) More soluble in plasma, (C) Less molecular weight, (D) Less PCO2 in the alveoli
Answer is B. Diffusion of Gases Through Liquids The more soluble a gas is, the faster it will diffuse. In this case carbon dioxide diffuses much faster than oxygen, as it is much more soluble. Ref: guyton and hall textbook of medical physiology 12 edition page number:348,349,350