kapilsci

Conflict with two terms ? It is common in electrochemistry and solid-state physics to discuss both the  chemical potential  and the electrochemical potential of the  electrons . However, in the two fields, the definitions of these two terms are sometimes swapped. In electrochemistry, the electrochemical potential  of electrons (or any other species) is the total potential, including both the (internal, nonelectrical) chemical potential and the electric potential, and is by definition constant across a device in equilibrium, whereas the  chemical potential  of electrons is equal to the electrochemical potential minus the local  electric potential energy  per electron.  In solid-state physics, the definitions are normally compatible with this,  but occasionally  the definitions are swapped.

Definition of Conductivity Conductivity is the ability of a material to conduct electric current. The principle by which instruments measure conductivity is simple—two plates are placed in the sample, a potential is applied across the plates (normally a sine wave voltage), and the current that passes through the solution is measured. Conductivity (G), the inverse of resistivity (R), is determined from the voltage and current values according to  Ohm's law. G =   1   R =  I (amps)  E (volts) Since the charge on ions in solution facillitates the conductance of electrical current, the conductivity of a solution is proportional to its ion concentration. In some situations, however, conductivity may not correlate directly to concentration. The graphs shown here illustrate the relationship between conductivity and ion concentration for two common solutions. Notice that the graph is linear for sodium chloride solution, but not for highly conce...

 Structure activity relationship of methyldopa

Applications of conductivity measurements: Calculating the solubility product of a partially soluble salt (Lab report) Theory The solubility of poorly soluble salts is expressed as the solubility product. That is the product of the concentration of ions in the solution which are in equilibrium with the solid ion. These concentrations can be determined via conductivity measurements. In this practical PbSO 4  is used.                                  PbSO 4  ⇌  Pb 2+  + SO 4 2- Assume concentration of solid is a constant. Concentration of Pb 2+ = concentration of SO 4 2-  = C                               \   Ksp = [Pb 2+ aq ] [SO 4 2- a...