Get premium membership and access revision papers, questions with answers as well as video lessons.

Sch 404: Instrumental Methods Question Paper

Sch 404: Instrumental Methods

Course:Bachelor Of Science

Institution: Kenyatta University question papers

Exam Year:2010

INSTRUCTIONS
Answer ALL questions
Q1 a) A popular molecular spectroscopic technique for quantitative analysis is UV- Visible spectrophotometry.
(i) State the law under which it is based.
(ii) Describe the causes of nonlinearity experienced at high sample concentration.
(iii) Draw a labelled block diagram of the optical parts of a double beam UV-Vis instrument and explain its advantages over a single beam instrument. [10 marks]
b) In atomic spectroscopy atomization is an important procedure of analysis.
(i) Using a diagram explain the process of nebulization used in flame atomization.
(ii) Using an example, describe the chemical process taking place in the flame.
(iii) Briefly explain the experimental procedure of analyzing sodium in a water sample. [12 marks]
Page 2 of 2
c) (i) Explain the causes of radiation absorption by a molecule in the mid- infrared region of the electromagnetic spectrum.
(ii) Name the types of vibrations a molecule usually undergoes.
[6 marks]
Q2 a) Write brief notes on the following terms
(i) Differential thermal analysis
(ii) Chemical ionization in MS
(iii) Chemical shift and Spin-spin splitting in NMR
(iv) Solid state membrane in potentiometry [16 marks]
b) Using a diagram, explain the working of hollow cathode lamp used in AAS [6 marks]
Q3 a) (i) Draw a polarogram and explain its main features.
(ii) State the advantages of using a dropping mercury electrode in polarography. [8 marks]
b) Analysis in radiochemical techniques depends upon the radioactivity of the solute.
(i) Name the particles/radiation emitted from radionuclides.
(ii) Explain how activation analysis is carried out.
(iii) 10 mg of a labelled analyte, with specific activity of 18870cpm was added to the mixture analysed. After thorough mixing, 1.5mg of the pure analyte was separated and its specific activity was found to be 1550cpm. What was the amount of the analyte in the original sample?
[12 marks

Sch 404: Instrumental Methods Question Paper

More Question Papers

Popular Exams