Stripping voltammetry is a highly sensitive electroanalytical technique for the determination of heavy metals. The analysis involves two steps: (1) accumulation step: applying a potential to reduce metal ions to metal and deposit it on an electrode surface (2) stripping step: scanning the potential in the positive direction to oxidize the deposited metal on the electrode surface to ions. The sensitivity of the method can be controlled by the deposition time and other parameters. In a stripping voltammetric measurement of Cd2+, deposition is undertaken at 5.00 × 10-6 A for 2 minutes. Calculate the mass of Cd (unit gram) deposited on the electrode surface (atomic weight of Cd is 112.4). Answer:

Stripping voltammetry is a highly sensitive electroanalytical technique for the determination of heavy metals. The analysis involves two steps: (1) accumulation step: applying a potential to reduce metal ions to metal and deposit it on an electrode surface (2) stripping step: scanning the potential in the positive direction to oxidize the deposited metal on the electrode surface to ions. The sensitivity of the method can be controlled by the deposition time and other parameters. In a stripping voltammetric measurement of Cd2+, deposition is undertaken at 5.00 × 10-6 A for 2 minutes. Calculate the mass of Cd (unit gram) deposited on the electrode surface (atomic weight of Cd is 112.4). Answer:

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.28QAP

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