常温下，某酸H3A水溶液中含A的各种粒子的分布分数(平衡时某种粒子的浓度占各粒子浓度之和的分数)与pH关系图如下所示，下列说法正确的是_刷题宝

题干

常温下，某酸H₃A水溶液中含A的各种粒子的分布分数(平衡时某种粒子的浓度占各粒子浓度之和的分数)与pH关系图如下所示，下列说法正确的是（）

A：NaH₂A水溶液呈碱性

B：H₃A溶液中存在:c(H⁺)=c(OH^-)+c(H₂A^-)+ $\frac{1}{2}$ c(HA^2-)+ $\frac{1}{3}$ c(A^3-)

C：向H₃A溶液中加入一定量的NaOH溶液至pH=5时， $\frac{c (H A^{2 -})}{c (H_{3} A)} = 10^{0.6}$

D：向H₃A溶液中加入氨水使PH从5→9发生的主要离子反应是:H₂A^-+OH^-=HA^2-+H₂O

上一题下一题 0.0难度选择题更新时间:2020-01-05 05:21:55

答案(点此获取答案解析）

C

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