Part C
Each question carries 10 marks

17. (a) Why does a signal for a particular set of protons split into a multiplet? Give number of
signals, peak ratio and multiplicity of different sets of protons in the NMR spectrum of 1-
bromopropane.

(b) Give a neat and labelled sketch of instrumentation of UV-visible spectrometer.
(€) Write ೩ note on vibrational modes of carbon dioxide molecule. State which of these modes
are IR active; andgive reason for their activity. (4+3+3)

OR

18. (a) What is chemical shift? Write the cause of chemical shift.
(0) CO molecule absorbs at 2140௦௩. Calculate the force constant of the molecule, given
atomic masses of C and 0 are 120 and 16 u respectively 10 =1.67 x 10712.
(c) What are the various energy transitions possible in a molecule? Why does electronic
spectrum appear broad? (4--3--3)

19. (a) Design a reversible cell for the reaction;
2AK(s) +3Fe”* ‏جم‎ 2617 (aq) +3Fe s) Derive Nernst equation for the cell.
(b)Explain the variation of emf of Daniel cell with respect to temperature and concentration.
(5+5)
OR

20. (a)Draw a well labelled diagram of calomel electrode. Write electrode reaction and
representation of the electrode.
(b) Find the potential of hydrogen electrode at 25°C for solution of pH=0 and pH=14
(c)Why Aluminium metal when reacts with acid and base liberates 13) gas; whereas Fe metal
can liberate 13) only from acids. E°Al**/Al=-1.66V and E°Fe”*/Fe=-0.44V

(41343)

21. (a)Explain the principle and instrumentation of HPLC.
(b)Differentiate between DTA thermogramand TGAthermogram graphically. Give one
important application of each type. (5+5)

OR

22. (a)Give a comparison of GSC and GLC.
(b)Write the working of TLC. List the important applications. (5+5)

23. (a)Give the classification of conducting polymers and write the mechanism of conduction in
them.
(b)Write structural formulae and important uses of the polymers Kevlar and ABS.
(6+4)