How to calculate the no. of molecules of a gas that bring about a unit change in intracellular pH?

Hi everybody, If I allow a gas to permeate through the cells?membrane, the intracellular pH would change. I can determine this change in pH (assume that the pH increased from 6.0 to 6.5) but I need to know the Number of gas molecules that were responsible to bring about this pH change. Both the buffers (the one serving as source of a gas and the other containing the cells) have the same pH before mixing. Also the molarity of the gas source is known. Thanks in advance for your information. SaadHow to calculate the no. of molecules of a gas that bring about a unit change in intracellular pH?
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