Master of Science II (Physical Chemistry)
Examination: Oct Nov 2016 Semester III (New CBCS)
SLR No. Day
Date Time Subject Name Paper No. Seat No.
SLR SD
242
Friday
18/11/2016
02:30 P.M
to
05:00 P.M
Electrochemistry
C
XI
Instructions: Attempts in all five questions.
All questions carry equal marks.
Q.1 is compulsory.
Answer s to all questions should be written in same answer book.
Attempt any two questions from Section I and any two questions
from section II.
Figures to the right indicate full marks.
Neat and labeled diagrams should be drawn wherever possible.
Use of log table and calculators in allowed.
Total Marks:70
SECTION I
Q.1 Answer the following: (One mark each) 14
Write the expression for the constant B in Debye-Huckel- Onsager equation.
Write the expression for hydration energy of a negative ion according to Bernal and
Fowler method.
In Gemini and Appolo fuel cell what is the electrolyte used?
The electrocapillary curve is obtained by plotting against
Write the equation for efficiency of a fuel cell.
The slope of Tafel plot for overvoltage is
Which electrolyte is used in natural gas CO-Air fuel cell?
What is biochemical corrosion?
Destruction of material due to its reaction with environment is called
Name the mechanism with which the abnormal conductance of hydrogen ion is
explained.
Give the expression for thickness of ionic atmosphere.
What is first postulate of Debye-Huckel theory of interionic attraction?
As the concentration of electrolyte increases the thickness of ionic atmosphere
decreases True or False.
The mobility of ion due to electrophoretic force. (decreases/ increases)
SECTION II
Q.2 Obtain an expression for the potential on the ion due to ionic atmosphere for dilute
solution.
07
Explain Bjerrum theory in detail. 07
Page 1 of 2
Q.3 What is decomposition potential? Give experimental method for the determination of
decomposition potential.
07
Calculate the ratio of activity coefficient fx,fc and fm for 0.1 N KI in ethyl
alcohol at 25oC. The densities of pure solvent and solution are 0.7919 and 0.8014
respectively.
07
Q.4 Explain briefly the experimental determination of heat of hydration of hydrogen ion. 07
Give an account of qualitative verification of Debye-Huckel equations for activity
coefficients.
07
SECTION II
Q.5 Discuss in brief the metal corrosion prevention. 05
What is difference in between overvoltage and polarization? Explain types
polarization.
05
Calculate the Debye-Huckel constants A and B for water at 25oC. (D=78.6 and
ŋ=8.95x10-3 poise)
04
Q.6 Explain in brief the streaming and sedimentation potential. 05
Calculate zeta potential of a quartz particle moving with a velocity of 3x10-3 cm/sec
in aqueous suspension under potential gradient of 10 V/cm (Given x 10-3
poise D=78.30 at 25oC)
05
Describe the van Arkel model for calculating the hydration energy. 04
Q.7 Write a note on any three of the following: 14
Debey Huckel Bronsted equation
Hydrogen- oxygen fuel cell
Types of polarization
Influence of ions on zeta potential.