Exam 2 Flashcards
In which electroanalytical method is a two-electrode system used?
Potentiometry
Which electroanalytical method has the smallest LOD for analyzing metal ions in water?
Differential Pulse Voltammetry (DPV)
Why is the solution purged with N2 before doing most voltammetric analysis?
To remove oxygen from the solution
What changes the measured cell potential?
increasing pH
decreasing pH
increasing pressure
What voltammetric technique is hydrodynamic?
Polarography
What will increase the maximum velocity of a photoelectron ejected from and element by visible light?
Changing light from visible to UV
Changing direction of beam by passing radiation at an angle through the interface between two transparent media is called?
Refraction
What is the basic process in lasers?
Stimulated emission
The magnitude of molar absorptivity of a compound depends on?
Wavelength of the radiation
Which technique is based on scattering of electromagnetic radiation and matter?
Raman Spectroscopy
Why do we use KNO3 with a relatively high concentration in the solution in voltammetric methods?
It is used as a background for the system.
It eliminates migration current
How to we use CV to distinguish reversible and irreversible electrochemical systems?
The sweep rate is used.
If the sweep rate in increased and Ep changes it is an irreversible system if not it is reversible.
What electrodes are used in Potentiometry?
Reference and Indicator
What electrodes are used in Constant Current Coulometry?
Generator
What electrodes are used in Voltammetry?
Working, Reference, and Auxilary
