LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
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B.Sc. DEGREE EXAMINATION – CHEMISTRY
FOURTH SEMESTER – April 2009
CH 4502 – ELECTROCHEMISTRY
Date & Time: 24/04/2009 / 9:00 – 12:00 Dept. No. Max. : 100 Marks
PART – A
Answer ALL questions. (10 x 2 = 20 marks)
- Define electromotive series. Give its application.
- What is a reversible cell?
- What is LJP? How can it be minimised?
- What are Fuel cells? Give its application.
- State Faraday’s first law of electrolysis.
- Distinguish between Strong and Weak electrolyte.
- Define the term activity of an electrolyte.
- Explain the principle involved in the conductometic titration of AgNO3.
- Define the term limiting current.
- Define Overvoltage.
PART – B
Answer any EIGHT questions. (8 x 5 = 40 marks)
- Explain the following with an example.
(i) Metal – Metal ion electrode.
(ii) Amalgam electrode.
- Describe the construction and working of Weston cell.
- Calculate the EMF of the concentration cell
Pt; H2(P1), HCl, H2(P2); Pt at 25oC.
If P1 = 600 torr and P2 = 400 torr.
- How will you determine the standard electrode potential of copper electrode.
- How will you determine the pH of a solution using glass electrode.
- Derive expressions for ΔG; ΔH and ΔS in terms of EMF of a cell.
- How is transport number determined by moving boundary method?
- Calculate the equivalent and molar conductivities of 0.08N H2SO4 solution
having specific conductivity 1.72 x 10-3 Scm-1.
- How is Kb of a weak base determined by conductance measurement?
- Discuss the principle and procedure for conductometric titration of a
Strong acid with a strong base.
- Discuss on the applications of decomposition potential.
- Explain the electrochemical theory of corrosion.
PART – C
Answer ANY FOUR questions. (4 x 10 = 40 marks)
- How is solubility of sparingly soluble salt determined by EMF measurements.
- (i) Derive the Nernst electrochemical equation.
(ii) Calculate the reduction potential of the electrode
Pt/Cl2(g) (1.15)atm/2Cl– (0.01M).
Given that EoCl2/2Cl– = 1.8V.
- What are concentration cells? Derive an expression for the EMF of an electrolyte for a concentration cell without transference.
- Explain any four applications of EMF.
- (i) Discuss the Arrhenius theory of electrolytic dissociation.
Give its limitations.
- Explain the principle involved in the potentiometric titrations.
- (i) Discuss on the Debye-Huckel theory of strong electrolytes.
(ii) Explain the principle of polarography.