试题与答案

下列溶液中各微粒的浓度关系一定正确的是( ) A.碳酸溶液中,H2CO3第一级

题型:选择题

题目:

下列溶液中各微粒的浓度关系一定正确的是(   )

A.碳酸溶液中,H2CO3第一级电离出H+的是第二级电离出H+的2倍

B.在Na2CO3和NaHCO3的混合溶液中:c(Na+)+c(H+)=c(HCO3-)+c(OH-)+c(CO32-

C.25℃时,pH=10的CH3COONa溶液与pH=l0的氨水中,由水电离出的c(OH-)之比为1:1

D.物质的量浓度相同的4种溶液①CH3COONa②NaNO3③Na2CO3④NaOH,pH的大小顺序是④>③>①>②

答案:

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参考答案:A

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