BCHET-141 · December 2024 · English
IGNOU BCHET-141 December 2024 Previous Year Question Paper
Analytical Methods In Chemistry
Structured previous year question paper for BCHET-141, December 2024 session.
Max marks: 50 · Questions: 17
Verified: 29 Jul 2026
B. SC. (GENERAL)
(BSCG)
Term-End Examination
December, 2024
BCHET-141 : ANALYTICAL METHODS IN
CHEMISTRY
Time : 2 Hours Maximum Marks : 50
Note :
(i) Answer any ten questions.
(ii) All questions carry equal marks.
Q1.(a) What are determinate errors ?
(b) The careful determination of iron in an iron-ore sample is carried out by gravimetric method by five students. The percentages found are :
Q2.48, 67.47, 67.37, 67.40 and 67.43 Find the standard deviation and average deviation. 24+3=
(5)
Q3.What are the usual properties of normal error curves ? Draw a normal error curve.
Q4.What are the types of reagents used for extraction by solvation ? Write the general structures of the following classes of compounds : 3+2=5
(a) Alkyl thiophosphoric ester
(b) Alkyl thiophosphonic ester
(c) Alkyl thiophosphinic ester
(d) Trialkyl phosphene sulphide
Q5.State batch extraction process. How will you separate salicylic acid from 1, 4- dibromobenzene ? 2+3=
(5)
Q6.(a) Write the general mechanism of separation in paper chromatography.
(b) Name any two stationary phases which can be used in column chromatography. 3+2=
(5)
Q7.A thermogram of a magnesium compound shows a loss of 91.0 mg from a total of 175.0 mg used for analyte. Identify the compound either as MgO, MgCOs or MgC20, (Atomic mass of Mg = 24.3 u).
Q8.Write short notes on the following (any two) : 24255
(a) Silver-Silver Chloride Electrode
(b) Saturated Calomel Electrode
(c) Glass Electrode
Q9.Describe the principle of Wheatstone bridge with the help of circuit diagram.
Q10.Define and differentiate between molar conductivity and equivalent conductivity.
Q11.Define
(i) polychromatic and
(ii) monochromatic radiations. For the wavelength
(A) = 450 nm, calculate its energy
(E) and wave number
(v). (h = 6.626 x 10-4 J-s and c = 3 x 108 m/sec). 24+3=
(5)
Q12.Write the factors which are responsible for the deviation from Beer-Lambert’s law.
Q13.Write the merits and limitations of flame atomic absorption spetrophotometry.
Q14.What are the applications of flame photometry ?
Q15.Describe them briefly.
Q16.(a) How many modes of vibration will be observed in IR spectrum of SOz molecule ?
(b) Explain the potential energy curve for harmonic and anharmonic oscillators. 24+3=
(5)
Q17.Describe the effect of furnace atmosphere on the TG curve with the help of an example. 5 नोट : 6) fee wed eam df
(i) Ot Wee are ware BY
Q18.48, 67.47, 67.37, 67.40 और 67.43 24355 ait c=3 x 108 ms) 243=
(5)