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Principles of Instrumental Analysis, 6th ed. Chapter 25
 
 2
limiting current when mass transport is by diffusion and migration and convection have 
been eliminated. 
 (g) Turbulent flow is a type of liquid flow that has no regular pattern. Laminar flow 
is a type of liquid flow in which layers of liquid slide by one another in a direction that is 
parallel to a solid surface. 
 (h) The difference between the half-wave potential E1/2 and the standard potential E0 
for a reversible reaction is shown by Equation 25-12 
 0 A
1/ 2 A ref
P
0.0592 log kE E E
n k
= − − 
 If the mass transfer coefficients kA and kP are nearly the same, . Hence, 
E
0
1/2 A refE E E≈ −
1/2 is often very nearly equal to E0 versus the reference electrode. 
 (i) In normal stripping methods, the analyte is deposited on a mecury drop or in a 
film by electrolysis. In adsorptive stripping methods, the analyte is deposited by physical 
adsorption. The deposited analyte is determined by stripping in the same way by the two 
methods. 
24-2. (a) A voltammogram is a plot of current as a function of the potential applied to a 
working electrode in an electrochemical cell. 
 (b) Hydrodynamic voltammetry is a type of voltammetry in which the analyte 
solution is vigorously stirred or caused to flow by an electrode thus causing the reactant 
to be brought to the electrode surface by convection as well as diffusion. 
 (c) The Nernst diffusion layer is the thin layer of stagnant solution that is 
immediately adjacent to the surface of an electrode.