Gujarat University 2005 B.Sc Chemistry -X - Question Paper

-04 4
Seat No. : ____________
TB-04
Chemistry Paper-X
Time : three Hours] [Total Marks : 70
Instruction : (1) All ques. carry equal marks.
(2) Attempt all ques..
1. ans any 3 of the subsequent : (14)
(a) How will you detect and determine a carbonyl group in an organic compound ?
(b) Write a note on Literature of Analytical Chemistry.
(c) explain the use of Cupferron in Inorganic analysis. What is the advantage of Neocupferron over Cupferron ?
(d) Write a note on sensitivity, accuracy and specificity of gravimetric methods using organic reagents.
(e) elaborate the different spectroscopic and spectrophotometric methods of analysis ? Compare them with electrochemical methods.
(f) discuss Gravimetric factor. compute the gravimetric factor for Nickel in Nickel dimethylglyozime and for Aluminium in Aluminium oxinate.
2. ans the subsequent : (14)
(a) discuss the origin of Residual current in polarography. explain the factors affecting limiting current.
(b) Giving examples, explain the principle involved in potentiometric titrations.
discuss the utility of Gran’s Plot.
(c) discuss the difference ranging from iodometry and iodimetry. Why iodimetric titrations are performed in neutral solutions and iodometric titrations are performed in acidic solutions ? Compare KMnO4 and K2Cr2O7 as titrants.
OR
TB-04 5
2. (a) Giving an illustration discuss the working mechanism of an ion-selective electrode. discuss its selectivity coefficient and its use.
(b) Why a small electrode is used in polarography ? discuss the function of supporting electrolyte and gelatin in polarography. Why 3 electrodes are used in polarography ?
(c) explain the potential requirements for redox titrations. discuss the function of a salt bridge.
OR
(c) explain the use of electrodes of the 1st kind, the 2nd type & the inert redox electrode in potentiometric analysis.
3. ans the subsequent : (14)
(a) What considerations govern the option of the carrier gas and stationary phase in chromatography ? define the fundamental difference ranging from adsorption and partition chromatography.
OR
(a) List the variables that lead to band broadening and band separation in chromatography. define any 2 detectors used in gas chromatography. elaborate their relative merits ?
(b) elaborate the essential components of a spectrophotometer ? define the function of every. Why is the sample compartment located ranging from the monochromator and the detector in UV-Vis spectrophotometer but ranging from the source and the monochromator in infrared spectrophotometer ?
Why cannot the excellent detector systems available for UV and visible radiations be used with infrared radiation ?

Earning:   Approval pending.