EDTA Complexometric Titration 1

2

:N-COO-CoNiZnCuCdHg EDTA 3

EDTA (H4Y, EDTA)Ethylene Diamine Tetra Acetic acid4

EDTANa2H2Y2H2O EDTAS=11.1g/100mL0.3molL-1pH=4.4

H6Y2+H5Y+H4YH3Y-H2Y2-HY3-Y4-pKa1=0.90pKa2=1.60pKa3=2.00pKa4=2.67pKa5=6.16pKa6=10.26Ka1Ka6:10-0.9010-1.6010-2.00, 10-2.6710-6.1610-10.26 KH1KH6:1010.26106.16102.67102.00101.60100.90 EDTA7(P1536-1).

6

Y4- EDTA H2Y 2-HY 3-Y 4- pH < 0.9 H6Y2+2.676.16 H2Y2- >10.26 Y4-7

1

000.00000004280.0000239970.00281291950.11172678480.8854362559

000.00000025230.00008931130.00660550980.16554129280.8277636338

000.00000143790.00032116480.01498745830.23698889130.7477010476

000.00000780610.00110010230.03239165050.32317151740.6433289237

00.00000000010.00003967810.00352818490.06554677630.41262100930.5182643513

00.00000000110.00018528590.01039542680.12185471090.48399661440.3835679609

00.00000000710.00077975230.02760302280.20415341290.51163075710.2558330477

00.00000004210.00290374110.06485715490.30266199710.47858368950.1509933753

00.00000021610.00941356650.13266433760.39061974560.38972134510.0775807891

00.00000095470.0262349870.23328179790.43339196340.27282292060.0342673763

00.00000360340.06247543430.35051715950.41087458990.1631959150.012933298

00.00001164890.12743394650.45111278240.33364539350.08361518080.0041810478

00.00003258560.22491871120.50237218580.23443669290.03707025610.0011695683

00.00008009740.34883357150.49160724480.14474990070.01444169850.000287487

00.00017620520.48419326130.43054518920.07998687710.00503522340.0000632439

00.00035383940.61348812950.34419627340.04034652770.001602530.0000127001

00.00066156070.72371850060.25619442490.01894827480.00047486450.0000023745

0.00000000010.001172720.80945802830.18079829670.00843712210.00013341180.0000004209

0.00000000040.00200114740.87152345350.12282282410.00361642180.0000360810.0000000718

0.0000000010.00332578910.9138916340.08126334630.00150971410.00000950370.0000000119

0.00000000250.0054282230.94114747270.05280288850.0006189530.00000245840.0000000019

0.00000000640.00874914160.95711791310.03388171960.0002505910.0000006280.0000000003

0.00000001610.0139717710.96438724840.02154028570.00010051980.00000015890.0000000001

0.00000004040.02214017560.96423093440.01358879850.00004001120.00000003990

0.00000010060.03481440580.95666302160.00850665830.00001580370.00000000990

0.00000024850.05424336820.94047368710.00527650860.00000618510.00000000250

0.00000060620.08348412420.91327989140.00323298650.00000239110.00000000060

0.00000145340.12629717070.87175334310.00194712410.00000090860.00000000010

0.0000034020.18652274660.81232870860.00114480570.000000337100

0.00000770770.26664057540.73270007810.00065151770.00000012100

0.00001675220.36565442060.63397309620.00035568930.000000041700

0.00003466870.47746000520.52232041240.00018490.000000013700

0.00006807420.59153779360.40830293060.00009119740.000000004300

0.00012703390.69649735040.30333286610.00004274840.000000001300

0.00022670170.78425042080.21550371460.00001916260.000000000400

0.00039029060.8518988580.14770256460.00000828680.000000000100

0.00065407550.90079896030.09854347570.0000034884000

0.00107533720.93442545770.06449776450.0000014406000

0.00174472750.95659388580.04166079960.0000005871000

0.00280547790.97052527760.02666900740.0000002371000

0.00448315020.97855060510.01696614950.0000000952000

0.00713126580.98212468070.01074401550.000000038000

0.01129996680.98192239880.00677761920.0000000151000

0.01783596970.97790513140.0042588930.000000006000

0.02801983930.96931657890.00266357940.0000000024000

0.04373469180.95461020030.0016551070.0000000009000

0.06762623440.93135490360.00101886160.0000000004000

0.1031395450.89624183310.00061862180.0000000001000

0.15419826060.8454335430.00036819630.0000000001000

0.2241979350.77558894140.00021312360000

0.31415832850.68572278060.00011889090000

0.42063463060.57930199630.00006337310000

0.53503963650.46492827230.00003209120000

0.64586931180.3541152660.00001542210000

0.74297026580.25702267150.00000706270000

0.82083153850.17916535520.00000310640000

0.87894898880.1210496870.00000132420000

0.92005068440.07994876380.00000055180000

0.94802191580.05197785790.00000022640000

0.96656269830.03343720980.00000009190000

0.97863891860.02136104440.0000000370000

0.98641498460.01358500060.00000001490000

0.99138524850.00861474550.00000000590000

0.99454712480.00545287280.00000000240000

0.99655253140.00344746760.00000000090000

0.99782202360.0021779760.00000000040000

0.99862468450.00137531540.00000000020000

0.99913179390.0008682060.00000000010000

0.99945202350.000547976500000

0.99965418020.000345819700000

0.99978177460.000218225400000

pH

Sheet1

0.12589254120.0010.99770006381.1138910102000.00000004280.0000239970.00281291950.11172678480.8854362559

0.02511886430.2010.62950618290.0751785002000.00000025230.00008931130.00660550980.16554129280.8277636338

0.00851138040.4010.39719154950.0052513626000.00000143790.00032116480.01498745830.23698889130.7477010476

0.00177827940.6010.25061092530.0003850942000.00000780610.00110010230.03239165050.32317151740.6433289237

0.00000057540.8010.15812480390.000030161200.00000000010.00003967810.00352818490.06554677630.41262100930.5182643513

01.0010.09977000640.000002571300.00000000110.00018528590.01039542680.12185471090.48399661440.3835679609

01.2010.06295061830.000000243200.00000000710.00077975230.02760302280.20415341290.51163075710.2558330477

01.4010.03971915490.00000002600.00000004210.00290374110.06485715490.30266199710.47858368950.1509933753

0.00000004791.6010.02506109250.000000003200.00000021610.00941356650.13266433760.39061974560.38972134510.0775807891

0.00002691531.8010.01581248040.000000000500.00000095470.0262349870.23328179790.43339196340.27282292060.0342673763

0.00316227772.0010.00997700060.000000000100.00000360340.06247543430.35051715950.41087458990.1631959150.012933298

0.12589254122.2010.0062950618000.00001164890.12743394650.45111278240.33364539350.08361518080.0041810478

2.4010.0039719155000.00003258560.22491871120.50237218580.23443669290.03707025610.0011695683

2.6010.0025061093000.00008009740.34883357150.49160724480.14474990070.01444169850.000287487

2.8010.001581248000.00017620520.48419326130.43054518920.07998687710.00503522340.0000632439

3.0010.0009977001000.00035383940.61348812950.34419627340.04034652770.001602530.0000127001

3.2010.0006295062000.00066156070.72371850060.25619442490.01894827480.00047486450.0000023745

3.4010.000397191500.00000000010.001172720.80945802830.18079829670.00843712210.00013341180.0000004209

3.6010.000250610900.00000000040.00200114740.87152345350.12282282410.00361642180.0000360810.0000000718

3.8010.000158124800.0000000010.00332578910.9138916340.08126334630.00150971410.00000950370.0000000119

4.0010.0000997700.00000000250.0054282230.94114747270.05280288850.0006189530.00000245840.0000000019

4.2010.000062950600.00000000640.00874914160.95711791310.03388171960.0002505910.0000006280.0000000003

4.4010.000039719200.00000001610.0139717710.96438724840.02154028570.00010051980.00000015890.0000000001

4.6010.000025061100.00000004040.02214017560.96423093440.01358879850.00004001120.00000003990

4.8010.000015812500.00000010060.03481440580.95666302160.00850665830.00001580370.00000000990

5.0010.00000997700.00000024850.05424336820.94047368710.00527650860.00000618510.00000000250

5.2010.000006295100.00000060620.08348412420.91327989140.00323298650.00000239110.00000000060

5.4010.000003971900.00000145340.12629717070.87175334310.00194712410.00000090860.00000000010

5.6010.000002506100.0000034020.18652274660.81232870860.00114480570.000000337100

5.8010.000001581200.00000770770.26664057540.73270007810.00065151770.00000012100

6.0010.000000997700.00001675220.36565442060.63397309620.00035568930.000000041700

6.2010.000000629500.00003466870.47746000520.52232041240.00018490.000000013700

6.4010.000000397200.00006807420.59153779360.40830293060.00009119740.000000004300

6.6010.000000250600.00012703390.69649735040.30333286610.00004274840.000000001300

6.8010.000000158100.00022670170.78425042080.21550371460.00001916260.000000000400

7.0010.000000099800.00039029060.8518988580.14770256460.00000828680.000000000100

7.2010.00000006300.00065407550.90079896030.09854347570.0000034884000

7.4010.000000039700.00107533720.93442545770.06449776450.0000014406000

7.6010.000000025100.00174472750.95659388580.04166079960.0000005871000

7.8010.000000015800.00280547790.97052527760.02666900740.0000002371000

8.0010.0000000100.00448315020.97855060510.01696614950.0000000952000

8.2010.000000006300.00713126580.98212468070.01074401550.000000038000

8.4010.00000000400.01129996680.98192239880.00677761920.0000000151000

8.6010.000000002500.01783596970.97790513140.0042588930.000000006000

8.8010.000000001600.02801983930.96931657890.00266357940.0000000024000

9.0010.00000000100.04373469180.95461020030.0016551070.0000000009000

9.2010.000000000600.06762623440.93135490360.00101886160.0000000004000

9.4010.000000000400.1031395450.89624183310.00061862180.0000000001000

9.6010.000000000300.15419826060.8454335430.00036819630.0000000001000

9.8010.000000000200.2241979350.77558894140.00021312360000

10.0010.000000000100.31415832850.68572278060.00011889090000

10.2010.000000000100.42063463060.57930199630.00006337310000

10.401000.53503963650.46492827230.00003209120000

10.601000.64586931180.3541152660.00001542210000

10.801000.74297026580.25702267150.00000706270000

11.001000.82083153850.17916535520.00000310640000

11.201000.87894898880.1210496870.00000132420000

11.401000.92005068440.07994876380.00000055180000

11.601000.94802191580.05197785790.00000022640000

11.801000.96656269830.03343720980.00000009190000

12.001000.97863891860.02136104440.0000000370000

12.201000.98641498460.01358500060.00000001490000

12.401000.99138524850.00861474550.00000000590000

12.601000.99454712480.00545287280.00000000240000

12.801000.99655253140.00344746760.00000000090000

13.001000.99782202360.0021779760.00000000040000

13.201000.99862468450.00137531540.00000000020000

13.401000.99913179390.0008682060.00000000010000

13.601000.99945202350.000547976500000

13.801000.99965418020.000345819700000

14.001000.99978177460.000218225400000

Sheet1

pH

Sheet2

Sheet3

-EDTA(M-Y):1.2.1:13.MHYMOHY,,1:14.MY(P155)8

MY H+pHpM9

10

(KMYEt)11

M + L = MLML + L = ML2

MLn-1+L=MLn[MLn]=n[M][L]n12

M + L = ML(1) M + L = ML ML + L = ML2

M+2L=ML21 [ML]= 1[M][L]1 [ML2]=2[M][L]21. ML(1:1) 2. MLn(1:n) 1:1 13

(2) M + L = ML ML + L = ML2

ML2+ L=ML3 M + 3L=ML3[ML3]=3[M][L]314

(3) M + L = ML ML + L = ML2

ML2+L=ML3

MLn-1 + L=MLn

:M+nL=MLnn=K1K2Kn=[MLn]=n[M][L]n15

MLn MLn=MLn-1+L MLn-1=MLn-2+L

ML= M + L

: MLn =M+nL MLn(K)(K)nn-1n 16

[H+] 17

18

19

6-1[NH3]=0.10molL-1,CZn2+=10-1.70molL-15a-b210a+10b10a20

24

Cu2+ + NH3Cu(NH3)2+ K1 = 104.18

Cu(NH3)2+ + NH3 Cu(NH3)22+ K2 = 103.48

Cu(NH3)22+ + NH3 Cu(NH3)32+ K3 = 102.87

Cu(NH3)32+ + NH3 Cu(NH3)42+ K4 = 102.11

: Cu2++4NH3Cu(NH3)42+

(K=K1K2K3K4=1012.6

23

1:4

0

12.6

1:2

2

19.6

1:1

3

20.6

25

Cu2+ + en Cu(en)2+ K1 = 1010.67

Cu(en)2+ + en Cu(en)22+ K2 = 108.93

Cu2++2enCu(en)22+ (=K1K2=1019.6

26

Cu2+ + tn Cu(tn)2+ (K1 = 1020.6

2 127

1.

2.

3.

2128

1.

2.

3.n

EDTA

29

30

Ca2+ CaY

31

3