Mid-Semester Exam 2021-22 Advanced Analytical Chemistry PDF

THE MAHARAJA SAYAJIRAO UNIVERSITY OF BARODA DEPARTMENT OF CHEMISTRY, FACULTY OF SCIENCE Mid-Semester Exam 2021-22 MSc - Semester I [3 ceredits] CHE2104C04 (Advanced Analytical Chemistry I) (Total Marks 30) Mo...

THE MAHARAJA SAYAJIRAO UNIVERSITY OF BARODA DEPARTMENT OF CHEMISTRY, FACULTY OF SCIENCE Mid-Semester Exam 2021-22 MSc - Semester I [3 ceredits] CHE2104C04 (Advanced Analytical Chemistry I) (Total Marks 30) Monday, 11.01.2021 Time : 11.00 am – 12.00 pm Q1 Answer the following questions as directed A Explain schematically how a substance can be purified by affinity chromatography? 2 What is immunoaffinity chromatography? B Two solutes have a separation factor of 1. 1. How many plates are required to give a 2 resolution of 1.0 ? If plate height is 0.1 mm, how long should the column be to get a resolution of 1.0? C Give the classification of electroanalytical methods in the form of a schematic. 3 D Differentiate between metallic indicator electrodes of second and third kind 3 OR Why do we need two mass transfer processes to explain band broadening ? Give the relationship to column and analyte properties for the two processes Q2 1 Consider the following compounds and their boiling points written in brackets: 2 Methyl cyclohexane (101°C), n-pentane (36°C), n-octane (126°C), 2,3-dimethyl octane (165°C), n-heptane (98°C). If these compounds are run on GC OV101 column, which compound will have the lowest and highest retention time? 2 Draw only labelled diagrams differentiating packed GC column and various FSOTs. Do 2 NOT write any description. 3 A mixture of n-heptane (boiling point 98.4°C), tetrahydrofuran (66.0°C), 2-butanone 3 (79.6°C), and n-propanol (97.0°C) is to be separated on two different columns, one non-polar and other, polar. Suggest which GC stationary phases can be used for the purpose. Also discuss the elution order of these compounds on the two columns. 4 Draw a neat schematic for FID and explain its working and characteristics. 3 Q3 1 Which of the following cannot be determined by TGA 1 a) % volatiles in coal. b) If the sample is of backing soda or washing soda. c) Melting point of an organic acid. d) % of moisture in a sample of cheese. 2 1  DTA curve of a polymer is given. The thermal events at A and B are a) mass loss due to evaporation of moisture and melting b) mass gain due to buoyancy and crystallization c) Glass transition and melting d) Glass transition and crystallization 3 The ferromagnetic alloys are used to calibrate a thermo-balance. Can these alloys be 1 used for the calibration of differential thermal analyzer? Justify your answer. 4 A thermogram of a magnesium compound shows a loss of 91.0 mg from a total of 175.0 2 mg used for analyte. Identify the compound either as MgO, MgCO3, or MgC2O4. [At M: Mg-24, C-12,O-16] 5 A 12.00 mg sample composed of Calcium Carbonate, Magnesium Carbonate and Silica 3 was analyzed by TGA. The resultant thermogram showed a mass loss of 3.0mg each in two steps. The first loss of 3.0mg at 480oC corresponds to the loss of carbon dioxide from MgCO3 and the second at 800 oC corresponds to the loss of carbon dioxide from CaCO3. What is the composition of the sample? [At M: Ca-40,Mg-24, C-12,O-16] OR Describe in brief, a method to determine boiling point of a highly volatile solvent by DTA. 3 Describe the effect of heating rate on thermal analysis in brief. 2 ________________