题目0.20mol/L的某碱溶液,其溶液的pH值为(Kb=4.2×10-4) ( )A. 2.04B. 11.96C. 4.08D. 9.920.20mol/L的某碱溶液,其溶液的pH值为(Kb=4.2×10-4) ( )A. 2.04B. 11.96C. 4.08D. 9.92题目解答答案B. 11.96