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Art PowerPoints Harris: Quantitative Chemical Analysis, Eight Edition CHAPTER 14: ELECTRODES AND POTENTIOMETRY
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CHAPTER 14: Figure 14.1 14-1 Reference Electrodes
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CHAPTER 14: Figure 14.2
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CHAPTER 14: Figure 14.3 Ag|AgCl|Cl - (xM) Reference Electrode
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CHAPTER 14: Figure 14.4
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CHAPTER 14: Figure 14.5 Calomel Electrode
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CHAPTER 14: Figure 14.6
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CHAPTER 14: Equation 14.18
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CHAPTER 14: Figure 14.7 Indicator Electrode
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CHAPTER 14: Equation 14.19 Potentiometric Titration
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CHAPTER 14: Figure 14.8 Potentiometric Titration
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CHAPTER 14: Equation 14.2
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CHAPTER 14: Equation 14.3
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CHAPTER 14: Figure 14.9 Junction Potential
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CHAPTER 14: Table 14.1
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CHAPTER 14: Table 14.2
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CHAPTER 14: Figure 14.10
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CHAPTER 14: Equation 14.20
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CHAPTER 14: Equation 14.21
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CHAPTER 14: Equation 14.4
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CHAPTER 14: Equation 14.22
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CHAPTER 14: Equation 14.5
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CHAPTER 14: Equation 14.23 pH Measurement with a Glass Electrode
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CHAPTER 14: Figure 14.11
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CHAPTER 14: Figure 14.12
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CHAPTER 14: Figure 14.13
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CHAPTER 14: Unnumbered Figure 14.7
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CHAPTER 14: Equation 14.6
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CHAPTER 14: Figure 14.14
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CHAPTER 14: Figure 14.15
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CHAPTER 14: Equation 14.7
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CHAPTER 14: Figure 14.16
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CHAPTER 14: Table 14.3a
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CHAPTER 14: Table 14.3b
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Errors in pH Measurement 1.Standards 2.Junction potential 3.Junction potential drift 4.Sodium error 5.Acid error 6.Equilibration time 7.Hydration of glass 8.Temperature 9.Cleaning
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CHAPTER 14: Figure 14.17 Junction potential drift
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CHAPTER 14: Figure 14.18 Acid and sodium (alkaline) error
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CHAPTER 14: Figure 14.18 Not all pH electrodes are glass IrO 2 (s) + H + + e - ↔ IrOOH(s) Can measure pH in a confined area or under extreme conditions. 14-6 Ion-Selective Electrodes 1.Glass membranes 2.Solid-state electrodes 3.Liquid-based electrodes 4.Compound electrodes
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CHAPTER 14: Equation 14.9 Selectivity coefficient The smaller the selectivity coefficient, the less the interference by X. Example: valinomycin : selective chelator of K + Response of ion-selective electrode
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CHAPTER 14: Equation 14.12 Using the selectivity coefficient Q: A fluoride ion-selective electrode has a selectivity coefficient of 0.1 for OH -. What will be the change in electrode potential when 1.0 x 10 -4 M F - at pH 5.5 is raised to pH 10.5? Solution At pH 5.5, E = constant – 0.05916log(1.0 x 10 -4 + (0.1)(10 -8.5 )) = constant + 236.6 mV At pH 10.5, E = constant – 0.05916log(1.0 x 10 -4 + (0.1)(10 -3.5 )) = constant + 229.5 mV Difference = -7.1 mV: quite significant!
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CHAPTER 14: Equation 14.12 Solid-State Electrodes
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CHAPTER 14: Figure 14.21
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CHAPTER 14: Table 14.5
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CHAPTER 14: Figure 14.22
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CHAPTER 14: Equation 14.13 Liquid-Based Ion-Selective Electrodes A hydrophobic membrane is impregnated with a hydrophobic ion exchanger called an ionophore.
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CHAPTER 14: Figure 14.27 Breakthrough in Ion-Selective Electrode Detection Limit Using a Metal Ion Buffer
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CHAPTER 14: Table 14.6
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CHAPTER 14: Figure 14.28 Compound Electrodes
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CHAPTER 14: Equation 14.14 Standard Addition with ISE S = βRT/nF
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CHAPTER 14: Equation 14.17 Metal Ion Buffers By changing the ratio of [MY n-4 ] and [EDTA], [M n+ ] can be determined. – metal ion concentration can be maintained constant.
![CHAPTER 14: Equation Metal Ion Buffers By changing the ratio of [MY n-4 ] and [EDTA], [M n+ ] can be determined.](http://images.slideplayer.com./34/10177054/slides/slide_50.jpg "– metal ion concentration can be maintained constant..")
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CHAPTER 14: Figure 14.31 14-8 Solid-State Chemical Sensors
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CHAPTER 14: Figure 14.32
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CHAPTER 14: Figure 14.33
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CHAPTER 14: Figure 14.34
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CHAPTER 14: Figure 14.35
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CHAPTER 14: Figure 14.37
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CHAPTER 14: Figure 14.36
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Homework Problems of Chapter 14 14-4, 9, 11, 16, 26, 33, 35, 40, 42, 45
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