常温下，向20mL 0.2mol/L H2A溶液中滴加0.2mol/L NaOH溶液．有关微粒的物质的量变化如图（其中Ⅰ代表H2A，Ⅱ代表HA﹣，Ⅲ代表A2﹣）所示．根据图示判断，下列说法正确的是

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常温下，向20mL 0.2mol/L H₂A溶液中滴加0.2mol/L NaOH溶液．有关微粒的物质的量变化如图（其中Ⅰ代表H₂A，Ⅱ代表HA^﹣，Ⅲ代表A²^﹣）所示．根据图示判断，下列说法正确的是（）

A：当V（NaOH）=20mL时，溶液中离子浓度大小关系：c（Na⁺）＞c（HA^﹣）＞c（A²^﹣）＞c（H⁺）＞c（OH^﹣）

B：等浓度的NaOH溶液与H₂A溶液按2：1混合后，其溶液中水的电离程度比纯水小

C：NaHA溶液中：c（OH^﹣）+c（A²^﹣）=c（H⁺）+c（H₂A）

D：向上述加入20mL NaOH溶液后所得溶液中再加入水的过程中，pH可能减少

上一题下一题 0.0难度选择题更新时间:2019-09-22 09:43:50

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C

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Zhang Lin is a middle school student. He is a good boy. Uncle Wu lives next to him. Uncle Wu has no child and can't see anything. He works in the factory (工厂) near Zhang Lin's school. He goes to work at 7:30 in the morning and comes home at 4:30 in the afternoon. Zhang Lin walks to school at 8:00 in the morning and comes home at the same time as Uncle Wu in the afternoon. On weekdays Zhang Lin gets up early to take Uncle Wu to the factory. After school he takes him home. On Sundays Zhang Lin helps Uncle Wu clean the house and do some cooking. Uncle Wu thanks Zhang Lin very much. He says, “Zhang Lin is a good boy. He is like my son.”

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