Worksheet Winkler
Name: Ma. Precious Lhyn Ordinario Date Perfomed: Oct.21, 2014
Co-worker’s Name: Emmanuel Hipe Date Due: Oct. 23, 2014
EXPERIMENT NO. 8
QUANTITATIVE DETERMINATION OF DISSOLVED OXYGEN CONTENT BY WINKLER REDOX TITRATION
A. Standardization of Thiosulfate Solution
Primary Standard used: KIO3
Formula Mass of Primary Standard: 214.0010 g/mol
%Purity: 99.9%
Formula Mass of KI: 166.00277 g/mol
%Purity of KI: 99.9%
Trial
1
2
3
KIO3 weight, g
0.1459
0.1458
0.1459
KI weight, g
1.0033
0.9857
1.0100
Volume of Na2S2O3, ml
Final Volume, ml
22.6
25.5
22.9
Initial Volume, ml
0.0
0.0
0.0
Net volume, ml
22.6
25.5
22.9
B. Sample Analysis
Volume of Sample: 400 ml
Volume of sample in aliquot: 50 ml
Trial
1
2
3
Volume of aliquot, ml
50
50
50
Volume of Na2S2O3, ml
Final Volume, ml
1.9
4.6
6.9
Initial Volume, ml
0.0
1.9
4.6
Net volume, ml
1.9
2.7
2.3
Co-worker’s Name: Emmanuel Hipe Date Due: Oct. 23, 2014
EXPERIMENT NO. 8
QUANTITATIVE DETERMINATION OF DISSOLVED OXYGEN CONTENT BY WINKLER REDOX TITRATION
A. Standardization of Thiosulfate Solution
Primary Standard used: KIO3
Formula Mass of Primary Standard: 214.0010 g/mol
%Purity: 99.9%
Formula Mass of KI: 166.00277 g/mol
%Purity of KI: 99.9%
Trial
1
2
3
KIO3 weight, g
0.1459
0.1458
0.1459
KI weight, g
1.0033
0.9857
1.0100
Volume of Na2S2O3, ml
Final Volume, ml
22.6
25.5
22.9
Initial Volume, ml
0.0
0.0
0.0
Net volume, ml
22.6
25.5
22.9
B. Sample Analysis
Volume of Sample: 400 ml
Volume of sample in aliquot: 50 ml
Trial
1
2
3
Volume of aliquot, ml
50
50
50
Volume of Na2S2O3, ml
Final Volume, ml
1.9
4.6
6.9
Initial Volume, ml
0.0
1.9
4.6
Net volume, ml
1.9
2.7
2.3