题目内容

已知H3PO4的pKa1=2.12.pKa2=7.20.pKa3=12.36,当溶液的pH为6.0时,则其各型体浓度的关系为:

A. [H3PO4]>[ H2PO4-]>[ HPO42-]
B. [ HPO42-]>[ PO43-]>[ H2PO4-]
C. [ HPO42-]>[ H2PO4-]>[ PO43-]
D. [ H2PO4-]>[ HPO42-]>[ H3PO4]

查看答案
更多问题

NaOH标准溶液滴定H3PO4至甲基红终点时的质子条件式是

A. [H+] + [H3PO4] = [OH-]+ [HPO42-] + [PO43-]
B. [H+] + [H3PO4] = [OH-] + [HPO42-] + 2[PO43-]
C. [H+] + 2[H3PO4] + [H2PO4-] = [OH-] + [PO43-]
D. [H+] + [Na+] = [OH-] + [H2PO4-] + 2[HPO42-] + 3[PO43-]

滴定反应tT+bB=cC+dD达计量点时,T的物质的量与B的物质的量的关系是()

A. 1:1
B. t:b
C. b:t
D. c:d

Cmol/LNH4H2PO4溶液的质子条件式为()

A. [H+]+[H3PO4]+[H2PO4-]=[OH-]+2[PO43-]+[NH3]
B. [H+]+[H3PO4]+[HPO42-]=[OH-]+2[PO43-]+[NH3]
C. [H+]+[H3PO4]=[OH-]+2[PO43-]+[NH3]+[HPO42-]
D. [H+]+[H3PO4]=[OH-]+[PO43-]+[NH3]+[HPO42-]

对于HAc(c1)+HCN(c2)溶液的质子条件式为()

A. [H+]=[OH-]+[CN-]+[Ac-]+c1
B. [H+]+[HCN]+[HAc]=[OH-]+c1+c2
C. [H+]=[OH-]+[CN-]+[Ac-]+c2
D. [H+]+[HCN]+c2=[OH-]+c1+[Ac-]

答案查题题库