![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
[主观题]
已知H3PO4的pKa=2.12,pKa=7.20,pKa=12.36.求其共轭碱PO43-的pK
b1,HPO42-的pKb2和H2PO4-的pKb3.
查看答案
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
含H2SO4(Mr=98.07)和H3PO4(Mr=98.00)的混合液两份(体积均为25.00mL),分别用0.1018mol·L-1的NaOH标准溶液滴定。第一份以甲基橙(pKHn=3.4)作指示剂,需25.18mL 滴至终点;第二份以酚酞(pKHn=9.1)作指示剂,需35.22mL到达终点。试求混合液中每种酸的浓度?(已知H3PO4的Ka1=10-2.12,Ka2=10-7.21,Ka3=10-12.7)
A.[H3PO4]〈0.010mol·dm-3
B.[H2PO- 4]〉[HPO2- 4]
C.[H+]〉0.010mol·dm-3
D.[OH-]〉[PO3- 4]
A.Na2HPO4和H3PO4
B.Na2HPO4和NaH2PO4
C.Na2HP4和H2CO3
D.Na2HPO4和Na2CO3
E.Na2HPO4和NaHCO3
A.#图片0$#
B.#图片1$#
C.#图片2$#
D.#图片3$#
A.KCl、HBr、HI
B.HCl、H2SO4、H3PO4
C.KOH、NaOH、Ca(OH)2
D.HCl、CH3COOH、NH3·H2O