PbpPb151Et10VpPb10VpPb27
K
PbY
CspPb
lgKPbYlgKPbYlgYH18046451159
b
11593pPbsp2730
pPbep70
pPb030
Et10VpPb10VpPb0007
K
PbY
CspPb
f15解
由Ksp,测Th时pH32测La时pH84,查酸效应曲线(数据)可知,测Th时pH2较好,为消除La的干扰,宜选pH25因此侧Th可在稀酸中进行;侧La在pH56较合适,可选在六亚甲基四胺缓冲溶液中进行。
18解由题意可知
S
0033511869021000
100
6231
Pb
0035000330003352072020001000
100
3729
21解据题中计量关系得:
002500300036000110254221009845
02014
24解据题中计量关系得:
Ni
0058310026145869310007176
6333
Fe
003544005831
00261407176
005831555845
100
2110
Cr
00500583100062100631600354400583155199607176
1001655)
f第7章氧化还原滴定法
1解:查表得:lgKNH3946EEθZ
2Z
00592lgZ
22
076300592lgZ
NH342KNH342104V
3解:EHg22HgEθHg22Hg0500592lgHg207930500592lgKspCl2
EθHg22Hg079300295lgKsp0265VEHg22Hg02650500592lg1Cl20383V
5解:EM
O4M
2Eθ′M
O4M
20059lg(M
O4M
2)5当还原一半时:M
O4M
2故EM
O4M
2Eθ′M
O4M
2145VCr2O720005molLCr32005010molLECr2O72Cr3Eθ′Cr2O72Cr300596lg(Cr2O72Cr3)101V
7解:Cu2Ag+=Cu2++2AglgK=(0800337)20059=1569K=101569=Cu2+Ag+2表明达到平衡时Ag+几乎被还原因此Ag+200520025molLAg+Cu2+K0523109molL
9解:2S2O32I33IS4O62a当滴定系数为050时,I3005002000100020001000001667molLI050021000200010001200030000700molL
f故由Ner
st方程得:EEI3I00592lg00166707000506V
b当滴定分数为100时,由不对称的氧化还原反应得:EI3I054500295lgI3I31ES4O62S2O32008000295lgS4O62S2O32221422得:6Esp2340059lgI32S4O62I6S2O322由于此时S4O622I3,计算得S4O620025molLI055molL代入上式Esp03900596lgS4O624I60384V
c当滴定分数为15EES4O62S2O3208000295lgS4O62S2O322此时S4O6201000200010000200molLS2O3201001000500000200molL故E080000295lg020002002130V
11.解:Ce4Fe2Ce3Fe3终点时CCe3005000mollFe2005000moll所以CCe4CCe3100941440059171010moll
CFe2r