Blood plasma is buffered to maintain near-neutral conditions inside the human body
CHEMISTRY · Multi-part · A Level · Chemistry · Acids and bases · Acids and bases
Problem
Blood plasma is buffered to maintain near-neutral conditions inside the human body. At 37 °C, the autoionization constant of water is Kw=2.5×10−14. A medical technician analyzes a sample and finds [H3O+]=1.6×10−7M.
(a) Calculate the pH of the blood plasma sample.
(b) Determine pKw at 37 °C and then calculate the pOH of the sample.
(c) Relative to neutrality at 37 °C, classify the plasma as acidic, basic, or neutral and support your classification with numerical evidence.
(d) Discuss qualitatively how a change of ±1 °C in body temperature could influence the criterion for neutrality and why very tight physiological control of pH is necessary.