An acid–base buffer system

A. True Or a mixture of a weak base with its conjugate acid.

B. False It can be a mixture of carbonic acid and bicarbonate ions.

C. False It minimizes, but does not prevent, pH change.

D. True pH=pK+log [base]/[acid]; log 1=0.

E. False pK should be near blood pH, which is 7 4.