ＫＥＭ Application Note
No.TIQ-12320
K yo t o E l e c t r o n i c s
Oxidation-Reduction titration
N o . N Z 2 2 - 1 2 2 9 6
Concentration of chromium(VI) oxide(chromic anhydride) in
plating solution
－Abstract－
Titrated chromium ( Ⅵ ) oxide with 0.1mol/L-sodium thiosulfate to determine
concentration from titration volume. The maximum inflection point was determined to
be the endpoint.
－Equipment－
Main unit：Automatic potentiometric titrator
Detector：Standard preamplifier
Combination Pt electrode
－Reagent－
AT-510
STD-510
C-272 + #429-0012
Titration solution：0.1mol/L-sodium thiosulfate solution
Additive ：Ammonium fluoride
3mol/L-sulfuric acid
Potassium iodide
－Method－
(1) Added 20g chromic anhydride to pure water to make it total 100mL.
(2) Added 5mL of (1) diluted solution to pure water to make it 50mL.
(3) Added 5mL of (2) to 200mL beaker, and added 1.0g ammonium fluoride to dissolve.
(4) Then, added 10mL 3mol/L-sulfuric acid, and added 2.0g potassium iodide.
(5) Added pure water to make it total 100mL.
(6) Titrated with 0.1mol/L-sodium thiosulfate to obtain concentration.
－Calculation－
Concentration (g/L)：(EP1-BL1)×TF×C1×K1/(SIZE×R)
EP1: volume (mL)
BL1: blank (mL)=0
TF: factor =1.0
SIZE: sample size (mL) K1: unit conversion=1 R: dilution ratio=0.1
C1: concentration conversion coefficient (0.1M-Na2S2O3･5H2O 1mL≡3.333g-CrO3)
－Ambient condition－
Room temperature：22.5°C
Humidity：47%
Weather：cloudy
－Reference－
京都电子工业株式会社 - 可睦电子(上海)商贸有限公司
电话: 021-54488867
电邮: [email protected]
上海市中山西路 2366 弄 1 号 203 室
网址: http://www.kem-china.com
No.TIQ-12320
-Titration parameteer[Titration Parameter]
Date : 2012/06/23 09:19
Sample ID
: CrO3
Method No. : 10
<Auto Titration>
Method Name :
Chromium Oxide
Dose Reagent Name:
0.1M/L-Na2S2O3
Titr Reagent Name:
0.1M/L-Na2S2O3
Method Type : Titration
-Titration curve<Calculation>
Calc. Type
: Sample
Conc.1
: Set
CO1=(EP1-BL1)*TF*C1*K1/(
SIZE*R)
*** Result ***
Unit
: g/L
EP No.
:1
Conc.2
: Off
Conc.3
: Off
Conc.4
: Off
Conc.5
: Off
Temp. Comp
: Off
Method No. : 10
<Auto Titration>
Method Name :
Chromium Oxide
<Constant>
C1(mg/mL)
K1
:
R
:
: 3.333
<Titration>
0.1
Form
: EP STOP
0.05
APB No.
:1
Unit No.
:1
<Dose Constant>
Detector No.
:1
Factor
: 1.005
Unit
:mV
Conc.
:
0.1
Max Volume
: 60.0
mL
<Titr.Constant>
Wait Time
: 20 s
Factor
: 1.005
Direction
: Auto
Conc.
:
0.1
Titr. Form
: EP STOP
<Control>
End Point No.
End Sense
End Point Area
Separation
Over Titr.Vol.
Gain
Data Samp.Pot.
Data Samp.Vol.
Control Speed
<Blank>
Blank 1
:
Sample No. : 25-01
Date : 2012/06/23 16:18
Sample ID
: CrO3
Titr. Time
: 00:07:24
Size
:
Conc-1
5mL
243.71g/L
End Point-1
Volume
Potential
: 36.5607mL
: 233.4mV
0.0
:1
: Auto
: Off
: Off
: 0.0 mL
:1
: 4.0 mV
: 0.5 mL
: Medium
－Results－
Run
Size (mL)
1st
5
2nd
5
3rd
5
Vol. (mL)
36.5607
36.6214
36.5352
Conc. (g/L)
243.71
244.12
243.54
京都电子工业株式会社 - 可睦电子(上海)商贸有限公司
电话: 021-54488867
电邮: [email protected]
Mean
SD
RSD
Statistics
243.79g/L
0.2982g/L
0.1223%
上海市中山西路 2366 弄 1 号 203 室
网址: http://www.kem-china.com