IGNOU BCHET-141 December 2022 Previous Year Question Paper

Q1.What is the Q test ? Explain with the help of an example.

Q2.What is a determinate error ? List the different sources of determinate errors.

Q3.(a) Differentiate between distribution coefficient and distribution ratio. 3

(b) Write the full form of the following : 2 @ TBP

(0) TBBP

Q4.Briefly explain batch extraction with the help of a suitable diagram.

Q5.Explain the principle of paper chromatography using suitable diagram.

Q6.(a) List the characteristics of an adsorbent used in column chromatography. Give examples of any two adsorbents. 3

(b) How can a adsorbent be activated ? Give an example.

Q7.(a) Write the general equation when a metal ion Mj,q) is exchanged with : 3 @) a weak cation exchanger

(ii) a strong cation exchanger

(b) What is the dry weight total capacity of a resin ? How is it expressed ?

Q8.Describe the factors which affect the conductivity of an electrolyte solution.

Q9.Write the factors which limit the accuracy of the pH measurements.

Q10.Write the steps involved in the thermodecomposition of a sample of monohydrate of calcium oxalate and also draw TGA curve for this process.

Q11.(a) Define frequency of an electromagnetic radiation and give its relationship with wavelength. 2

(b) An electromagnetic radiation has a wavelength of 650 nm. Calculate : 3

(6). the energy of a photon of the radiation

(1) the wave number of the radiation

Q12.(a) List different types of species that may absorb radiation in the UV-Vis region of the spectrum. Which of these would involve d-d transition ? 2 List different qualitative applications of UV-Vis spectrometry. Name any radiation source used in AAS.

(b) The absorbance of 2.0x10-* moldm=? solution of a substance taken in a cuvette of the path length of 1.0 cm is found to be

Q13.3. Calculate the molar absorptivity of the substance.

Q14.(a) Describe the different types of vibrations of a linear triatomic molecule of AB, type. 2

(b) Write the basic components of an IR spectrometer. What is the role of a transducer in it ? 3 Give any three advantages of FT-IR instruments over the dispersive IR instruments.

Q15.(a) What is the role of a radiation source in AAS spectrometry ? Name any one radiation source used in AAS. 2

(b) List any three methods of qualitative analysis by flame atomic emission spectrometry. 3 Describe any one of the qualitative application of flame atomic emission spectrometry. HA 650 nm @1 3 STH HAR AT AA TAT!