Exam 5: Electrochemistry

Question 1

Calomel

Answer 1

Often used for a reference electrode

HgCl2

Question 2

Coulometry

Answer 2

Only purpose is to measure Cl-

A form of electrochemical titration that uses 2 pairs of electrodes: generator and indicator

Question 3

4 parts of an electrochemical cell

Answer 3

Electrolyte solution
2 electrodes (half-cells)
Meter/power supply

Question 4

The potential measured by the Nernst equation is directly proportional to:

Answer 4

the logarithm of the ionic activity in the solution

Question 5

2 functions of an amplifier in a potentiometric meter

Answer 5

Provides stable amplification

Provides good noise rejection

Question 6

Another name for voltammetry

Answer 6

Polarography

Question 7

Conductimetry

Answer 7

The measurement of current flow between 2 electrodes

Question 8

The measurement of current flow between 2 electrodes

Answer 8

Conductimetry

Question 9

Lipemia/high protein levels interference with ISEs

Answer 9

Can interfere with indirect ISEs to cause falsely decreased results
Indirect ISEs measure a dilution of the sample - if a large amount of lipid or protein is taken instead of plasma to make the dilution, there will be fewer electrolytes to measure

Question 10

A calomel electrode would be immersed in:

Answer 10

A saturated KCl solution

Question 11

What antibiotic is contained in a liquid ion exchange membrane ion selective electrode for potassium?

Answer 11

Valinomycin

Question 12

Membrane in an oxygen sensing electrode

Answer 12

Polypropylene

Question 13

Membrane in a CO2 electrode

Answer 13

Silicone rubber

Question 14

Membrane in a direct ISE for sodium

Answer 14

Glass

Question 15

When using coulometry to measure serum chloride, what event indicates the end of the titration?

Answer 15

Silver ions generated in excess

Question 16

An advantage of using a direct ISE instead of an indirect ISE

Answer 16

Less potential interference from lipemia

Question 17

What is used to remove protein build-up from electrodes?

Answer 17

Pepsin

Question 18

Oxygen electrodes use the principle of:

Answer 18

Amperometry