Manipal University 2008 B.E Chemical Engineering FIFTH SEMESTER .(CHEMICAL) S/ Y, SUBJECT: CHEMISTRY – IV (CHM 301) - Question Paper
FIFTH SEMESTER B.E.(CHEMICAL) DEGREE exams
JUNE / JULY, 2008
SUBJECT: CHEMISTRY – IV (CHM 301)
REVISED CREDIT SYSTEM MANIPAL UNIVERSITY FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONS
MANIPAL UNIVERSITY FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONS
JUNE / JULY, 2008 SUBJECT: CHEMISTRY - IV (CHM 301)
MANIPAL UNIVERSITY
FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONSREVISED CREDIT SYSTEM
Time: 3hr._Max. Marks: 50
Note: Answer any FIVE full questions.
1. (i) Give reason: Polymorphism of substances can be studied by differential scanning calorimeter
and not by thermo gravimetric analysis.
(ii) Give reason: Triple headed reciprocating pump is more advantageous than the other pumps in HPLC instrument.
(iii) The distribution coefficient of iodine between CCl4 and water is 85. Calculate the conc. of I2 remaining in aqueous layer after extraction of 50 mL of 1.0 x 10-3 M I2 with one 50 mL portion and five 10 mL portions of CCl4 separately.
(2+2+6)
2. A compound with a molecular formula AC2O4.2H2O exists as AC2O4 between 150 - 200 0C, ACO2 between 280 - 320 0C, as AO above 450 0C. Another compound BH2P4O7 exists as BP4O6 between 140 - 350 0C and as BP2O above 400 0C. 323 mg. of the mixture containing above two compounds at 25 0C, on TG analysis, weighed 278 mg at 175 0C, 234 mg at 300 0C and 135 mg at 500 0C. Determine the composition of the mixture at 25 0C, if atomic weights of
A, B, C, H, O and P are 60, 40, 12, 1, 16 and 31 respectively.
(10)
3. Derive an expression for Beer - Lamberts law. Discuss in detail, the different types of deviations from Beer - Lamberts law. (10)
4. What are the different components of High Performance Liquid Chromatography (HPLC) instrument? Explain the instrumentation of HPLC with a neat diagram and also explain the elution of solutes by HPLC. (10)
5.A. Give reasons:
(i) Though there are four modes of vibration for CO2, only two IR absorption peaks are observed.
(ii) Saturated hydrocarbons are the most suitable solvents in the UV region.
5.B. The following data were obtained
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by GLC on a 40 cm packed column. | ||||||||||||
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Calculate (i) the average number of plates
(ii) the average plate height for the column
(iii) resolution for the compounds A and B
(iv) if the resolution of 1.5 was desired in resolving A & B, how long would the column have to be, if the same packing were employed? (4+6)
6.A. Write a short note on photo multiplier tube and scintillation detector.
6.B. If HCl35 is irradiated with 435.8 nm mercury line, calculate the Raman line in nm, if the fundamental vibrational frequency of HCl35 is 8.667 x 1013 sec-1.
MANIPAL UNIVERSITY FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONS
MANIPAL UNIVERSITY FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONS
JULY, 2008 (Make - up)
MANIPAL UNIVERSITY
FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONSSUBJECT: CHEMISTRY - IV (CHM 301)
MANIPAL UNIVERSITY
FIFTH SEMESTER B.E.(CHEMICAL) DEGREE EXAMINATIONSREVISED CREDIT SYSTEM
Time: 3hr._Max. Marks: 50
Note: Answer any FIVE full questions.
1. (i) Give reason: Helium is a suitable carrier gas in GLC when Differential Thermal
Conductivity Detector is used.
(ii) Write a short note on the preparation of plates for Thin Layer Chromatography (TLC).
(iii) Explain the isolation of chemical species from a natural product by Soxhlet solvent extraction technique with a neat diagram.
(2+2+6)
2. Explain the working of Heat flux and power compensated DSC with neat diagrams.(10)
3. The successive line separations in the rotational spectra of 12C16O and xC16O are 3.84235 cm-1 and 3.67337 cm-1 respectively. Calculate the isotope mass of xC. (10)
4. What are the different components of Gas Liquid Chromatography (GLC) instrument? Explain the instrumentation of GLC with a neat diagram and also explain the elution of solutes by GLC. (10)
5.A. Give reasons:
(i) Stokes lines are more intense than the anti-stokes lines.
(ii) It is not possible for a molecule to have zero vibrational energy.
5.B. The following data were obtained by GLC on a 40 cm packed column.
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compound |
tr (min.) |
Width of the peak (min.) |
|
Un retained species |
1.9 |
--- |
|
A |
10.9 |
0.82 |
|
B |
10.0 |
0.76 |
Calculate (i) the average number of plates
(ii) the average plate height for the column
(iii) resolution for the compounds A and B
(iv) if the resolution of 1.5 was desired in resolving A & B, how long would the column have to be, if the same packing were employed?
(3+7)
.A. Write a short note on production of X-rays.
.B. The fundamental vibrational frequency of HCl is 2890 cm-1. Calculate the force
1 27 35
constant of this molecule. The atomic masses are H = 1.673 x 10 Kg, Cl is 58.06
x 10-27 Kg. (4+6)
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Attachment: |
| Earning: Approval pending. |
