![Page 1: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/1.jpg)
Chapter 7 Electrochemistry
§7.3 Applications of Conductivity Measurement
![Page 2: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/2.jpg)
1. Monitor the purity of water
Silicon wafer
Integrated circuit
Fabrication of VLSI
§7.3 Applications of Conductivity Measurement
![Page 3: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/3.jpg)
1. Monitor the purity of water Fabrication of VLSI
§7.3 Applications of Conductivity Measurement
Silicon wafer
![Page 4: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/4.jpg)
In-situ monitoring of the cleaning
process: H2O2/H2SO4 → DW rinse →
dilute HF → SC-1 cleaning → DW
rinse → hot DW rinse → DW rinse →
SC-2 cleaning → DW rinse → dilute
HF → DW rinse.
DW⎯deionized water,
SC ⎯ standard cleaning:
SC-1: H2O2/NH3; SC-2: H2O2/HCl.
1. Monitor the purity of water Fabrication of VLSI
water Tap
water
Distilled
water
Deionized
water
Pure
water
/S·m-1 1 10-2 ~1 10-3 <1 10-4 5.478 10-6
§7.3 Applications of Conductivity Measurement
![Page 5: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/5.jpg)
2. Measure the ionizability and dissociation constant
m
( )c Z F U U
c + + + −+
=c+ =c
m ( )U U F + −= +
At infinite dilution
m ( )F U U
+ −= +
m
m
( )
( )
U U F
U U F
+ −
+ −
+= =
+
Arrhenius suggested that the degree of
dissociation of an electrolyte can be
calculated using molar conductivity.
§7.3 Applications of Conductivity Measurement
![Page 6: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/6.jpg)
22 2 2
m
m m m(1 ) 1 ( )
cc cK
c
= = =
− − −
Ostwald dilution law
Ostwald showed how one can measure the
dissociation constant of an acid.
The equation can be rearranged to
m2
m m m
1 1 1( )
a
cK
= +
Linearization
2. Measure the ionizability and dissociation constant
§7.3 Applications of Conductivity Measurement
![Page 7: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/7.jpg)
3. Determine solubility and solubility products
-Ag Ag Cl Cl H H OH OHc c c c + + − + + − −= + + +
w Ag Ag Cl Cl Ag Cl( )c c S + + − − + −− = + = +
w w
mAg Cl
S
+ −
− −= =
+
Example: The conductivity of a saturated
AgCl solution is 1.86 10-4 S·m-1, while
that of water used for preparation the
solution is 6.0 10-6 S·m-1. Given that the
molar conductivity of AgCl is 0.01372
S·mol-1·m2. Calculate the solubility
product for AgCl. What assumption have we made?
§7.3 Applications of Conductivity Measurement
![Page 8: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/8.jpg)
4. Determine ion product of water
Water can be taken as a dilute solution
of a strong electrolyte
CH+ = COH- = Kw1/2
m m,H m,OHc
+ −
= = +
The specific conductance of highly purified
water is 5.478 10-6 S·m-1. Calculate the
concentration of hydrogen ion in water.
-1 2
m m,H m,OH0.05481S mol m + −
= + =
6 1
1 2
m
4 3
7 3
5.478 10 S m
0.05481S mol m
0.9995 10 mol m
1 10 mol dm
c
− −
−
− −
− −
= =
=
§7.3 Applications of Conductivity Measurement
![Page 9: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/9.jpg)
5. Conductometric titration (the way to determine endpoint)
The conductance variation of a solution
during titration can serve as a useful
method to follow the course of the
reaction.
Na+ + OH- + (HCl) = Na+ + Cl- + (H+ + Cl-)
5.19 20.52 5.19 7.91 36.30
Precipitation reactions,
neutralization reactions,
coordination reactions
A
B
C
A’
B’
C’
V / ml
/
S·m
-1
endpoint
§7.3 Applications of Conductivity Measurement
![Page 10: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/10.jpg)
5. Conductometric titration
§7.3 Applications of Conductivity Measurement
![Page 11: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/11.jpg)
6. Study on ionic channel in cell membrane
§7.3 Applications of Conductivity Measurement
![Page 12: Chapter 7 Electrochemistry - Shandong Universitycourse.sdu.edu.cn/Download2/20201028212723969.pdf · Example: The conductivity of a saturated AgCl solution is 1.86 10-4 S·m-1, while](https://reader036.vdocuments.net/reader036/viewer/2022071414/610cef8f40bbaf6ab65085a1/html5/thumbnails/12.jpg)
6. Study on ionic channel in cell membrane
§7.3 Applications of Conductivity Measurement