BCHET-141 · June 2025 · English
IGNOU BCHET-141 June 2025 Previous Year Question Paper
Analytical Methods In Chemistry
Structured previous year question paper for BCHET-141, June 2025 session.
Max marks: 50 · Questions: 18
Verified: 29 Jul 2026
B. SC. (GENERAL) (BSCG)
Term-End Examination
June, 2025
BCHET-141 : ANALYTICAL METHODS IN
CHEMISTRY
Time : 2 Hours Maximum Marks : 50
Note:
(i) Attempt any ten questions.
(ii) All questions carry equal marks.
Q1.Explain the statistical significance of t-test and Q-test.
Q2.Measurement of glucose levels in a patient suffering from diabetes gave the following results :
Q3.108, 1.100, 1.122, 1.088, 1.115, 1.099 and
Q4.075 g/L. Calculate the 95% confidence interval when $= 0.019 g/L.
Q5.(a) Name the type of transitions involved in the UV-Visible, IR and Microwave spectroscopic techniques. 3
(b) What is the difference between elastic scattering and inelastic scattering ?
Q6.Differentiate between continuous and countercurrent extraction methods.
Q7.Write the general mechanism of separation of solutes in paper chromatography.
Q8.How does the mechanism change if get modify in case of paper impregnated with silica gel ?
Q9.Explain the concept of reverse phase chromatography and R; factor.
Q10.Explain the line spectra and band spectra with suitable diagrams.
Q11.How is the composition of metal complexes determined by Job’s method ? Explain with the help of Job’s graph.
Q12.What are ion exchangers ? Classify and give two examples of each type of them.
Q13.Draw a labelled diagram of the TG curve obtained by heating a mixture of 80 mg of CaC204.H20 and 80 mg of BaC204.H20 to 1200°C. Calculate the amount of all mass losses.
Q14.Write short notes on any two of the following : IEXQ=5
(a) Potentiometry
(b) Voltammetry
(c) Polarography
Q15.What is the principle of flame atomic emission spectrometry ? What are the uses of flame atomiser and atomiser burner in it?
Q16.0.32 g stainless steel sample was dissolved in HNOgz and the resulting solution was made to 100 cm® with water. Five standard solutions and the sample solution were aspirated into flame for the determination of nickel. The following observations were made: 5 Conc. of Ni (ppm) Absorbance 2 0.126 4 0.250 6 0.374 8 0.500 10 0.626 Sample 0.266 Calculate the percentage of Ni in the steel sample.
Q17.Referring to the infrared spectroscopy, explain the selection rules. Explain fundamental band, first overtone and second overtone in this context.
Q18.(a) Calculate the molar conductivity of KCl in aqueous solution : 3 Axci(5x10~ mold?) = 7.44x10Sm™ Ay,0 = 0.06 x10-°Sm™
(b) Explain the Beer-Lambert’s law.
Q19.108, 1.100, 1.122, 1.088, 1.115, 1.099 और
Q20.075 g/L (@) vara 3k ayers vat & da sia
Q21.80 mg CaC20..H20 sik 80 mg BaC20u.H20 2 0.126 4 0.250 6 0.374 8 0.500 10 0.626 Ago (5x10 mol/dm®) = 7.4410 Sm Ay, = 0.06 x10-°Sm™