Advanced Analytical Techniques for Inorganic Compounds — DU B.Sc (hons) Chemistry Previous Year Question Papers

DSE-Advance Analytrical Techniques for Inorganic B.Sc. (Hons.) Chemistry The questions should be numbered in accordance to the number in the question 1. a. Give one-line answers (any ]0): i. ICP-AEs is more sensitive than flame AES. ii. What are common impurities present in s61vents. iii. EPR more suitable than NMR for studying free radica]s. iv. UV-Vis spectroscopy is used for quantitative analysis. v. Quadrupole splitting occurs only in non-spherical environments. vi. Double beam specfrophotometers are more accurate. vii. Symmetric molecules sometimes show no IR absorption. viii. Smaller particle size improves separation in column chromatography. ix./ Fingerprint region is unique. x.. `Stronger bonds absorb at higher frequencies in IR spectra xi. Polar compounds elute slower in normal phase chromatography. xii. What type of radiation is used in M6ssbauer and EPR spectroscopy? xiii. Which bumer provides better flame stability _in FES? b. Describe the types of interactions responsible for spectral splitting in EPR. (5) 2. Write short notes on (any three): a. Advance drying techniques b. Resolution of column chromatography c. FT-IR interferometer (Michelson interferometer) d. Broadening of atomic spectral lines in A'ES e. Zero Field splitting in EPR 3. Give reasons (any five) a. b. c. d. e. f. Why are some drying agents unsuitable for certain solvents? Why do only paramagnetic substances show EPR spectra? Why do conjugated systems absorb at longer wavelengths? Why is regeneration of resin necessary? Why is recoil-free emission essential for M6ssbauer spectroscopy? Why is the premix buner.preferred in AAS? 4. Distinguish betvyeen the followings (any three): I a. Normal phase chromatography and reverse phase chromatography. b. c. d. e. Total co.nsumption burner and premix chamber bumer . Retention time and Retention volume EPR spectroscopy and M6ssbauer spectroscopy Absorption atomic spectra and emission atomic spectra a. Why is drying of solvents necessary? Describe different techniques for drying of -solvents and their principles. b. Discuss different type.s of electronic transitions and their relative energies occur in UV-Vis spectroscopy? c. Explain Hooke's law as applied to IR spectroscopy. Describe different types of molecular vibrations. d. Describe the h}perfine interactions (isomer shift, quadrupole splitting, magnetic splitting) in M6ssbauer spectroscopy. 6. Explain jn brief(any three) (3x5) a. Background correction in AAS b. Explain the preparation, purification, and handling of laboratory reagents in detail. c. Describe the mechanism of cation exchange with suitable equations. d. Write a note on g-value and ,its significance. e. Explain how IR spectroscopy is used for: (i) Functional group identification (ii) Structure elucidation