Download PTU (I. K. Gujral Punjab Technical University) MSc -Chemistry 2nd Semester May 2019 51152 ELECTROCHEMICAL TECHNIQUES Question Paper.
Roll No. Total No. of Pages : 02
Total No. of Questions : 19
M.Sc.(Chemistry) (Campus) (2015 to 2017) (Sem.-2)
ELECTROCHEMICAL TECHNIQUES
Subject Code : CHL-415
M.code : 51152
Time : 3 Hrs. Max. Marks : 70
INSTRUCTIONS TO CANDIDATES :
1. SECTION-A is COMPULSORY consisting of TEN questions carrying TWO marks
each.
2. SECTION-B contains SIX questions carrying FIVE marks each and students
have to attempt ALL questions.
3. SECTION-C contains THREE questions carrying TEN marks each and students
have to attempt any TWO questions.
SECTION-A
1. What is the role of liquid junction potential?
2. Given that
2
0
( )
0 76
Zn / Zn
E ? . V
?
? and
2
0
( )
0 34
Cu / Cu
E . V
?
? ? . Identify the cathode and anode
of the electrochemical cell.
3. Write down the relation between specific conductance and equivalent conductance.
4. Why calomel electrode is called reversible electrode?
5. What is anodic depolarizer? Give one example.
6. Write Nernst equation with meaning of the parameters involved.
7. How do you test for the irreversibility of a redox reaction in CV?
8. Mention the limitation of direct current polarography.
9. Draw the conductometric titration curve of weak acid with strong base.
10. How concentration cells are different from electrochemical cells?
SECTION-B
11. For the following cells, write down the cell reactions and calculate the EMF at 298K.
(a) Ag(s)|Ag
+
(a? = 0.1) || Zn
2+
(a? = 0.1)|Zn
Given the following standard potential values :
0
( )
0 799
Ag / Ag
E . V
?
? ;
2
0
( )
0 763
Zn / Zn
E ? . V
?
? ; Predict whether the cell reaction is
spontaneous or not.
FirstRanker.com - FirstRanker's Choice
1 | M-51152 (S39)-2065
Roll No. Total No. of Pages : 02
Total No. of Questions : 19
M.Sc.(Chemistry) (Campus) (2015 to 2017) (Sem.-2)
ELECTROCHEMICAL TECHNIQUES
Subject Code : CHL-415
M.code : 51152
Time : 3 Hrs. Max. Marks : 70
INSTRUCTIONS TO CANDIDATES :
1. SECTION-A is COMPULSORY consisting of TEN questions carrying TWO marks
each.
2. SECTION-B contains SIX questions carrying FIVE marks each and students
have to attempt ALL questions.
3. SECTION-C contains THREE questions carrying TEN marks each and students
have to attempt any TWO questions.
SECTION-A
1. What is the role of liquid junction potential?
2. Given that
2
0
( )
0 76
Zn / Zn
E ? . V
?
? and
2
0
( )
0 34
Cu / Cu
E . V
?
? ? . Identify the cathode and anode
of the electrochemical cell.
3. Write down the relation between specific conductance and equivalent conductance.
4. Why calomel electrode is called reversible electrode?
5. What is anodic depolarizer? Give one example.
6. Write Nernst equation with meaning of the parameters involved.
7. How do you test for the irreversibility of a redox reaction in CV?
8. Mention the limitation of direct current polarography.
9. Draw the conductometric titration curve of weak acid with strong base.
10. How concentration cells are different from electrochemical cells?
SECTION-B
11. For the following cells, write down the cell reactions and calculate the EMF at 298K.
(a) Ag(s)|Ag
+
(a? = 0.1) || Zn
2+
(a? = 0.1)|Zn
Given the following standard potential values :
0
( )
0 799
Ag / Ag
E . V
?
? ;
2
0
( )
0 763
Zn / Zn
E ? . V
?
? ; Predict whether the cell reaction is
spontaneous or not.
2 | M-51152 (S39)-2065
12. Write a short note on linear sweep voltammetry (LSV).
13. What is log-plot in polarography? Mention its characteristic physical significance.
14. The molar conductances of CH
3
COONa, HCl and NaCl at infinite dilution are 91?10
?4
,
426?10
-4
and 126?10
-4
Sm
2
mol
-1
respectively at 25?C. Calculate the molar conductance
at infinite dilution for CH
3
COOH.
15. Mention the merits and demerits of dropping mercury electrode (DME) used in
polarography.
16. Write a short note on oscillometry.
SECTION-C
17. Construct the Frost diagram of manganese from the following scheme :
1.7V 0.95V 1.5V -1.18V - 3+ 2+
4 2
MnO MnO MN Mn Mn ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
From this diagram justify that :
a) Mn
3+
is unstable,
b) MnO
2
is an oxidising agent,
c) Mn
2+
is the usual product of reduction of Mn (VII).
Can you use a nickel spatula to stir a solution of copper sulphate? Explain.
18. Differentiate between cathodic and anodic stripping methods. Draw a typical excitation
signal and voltammogram in case of striping method. Define microelectrode and mention
its advantages.
19. Specific conductance of a decimolar solution of KC1 at 18?C is 1.12 Sm
-1
.The resistance
of a conductivity cell containing the solution at 18?C was found to 55 ?. Calculate the
cell constant.
What is the effect of dilution on :
a) The specific conductance
b) The equivalent conductance of CH
3
COOH.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
FirstRanker.com - FirstRanker's Choice
This post was last modified on 05 December 2019