LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – CHEMISTRY

WD 02

FIRST SEMESTER – April 2009

CH 1502 – ANALYTICAL CHEMISTRY

 

 

 

Date & Time: 20/04/2009 / 1:00 – 4:00       Dept. No.                                                       Max. : 100 Marks

 

 

PART –A

Answer ALL the questions                                                                            (10 x 2 = 20 marks)

1. Mention the threshold limits of a vapour concentration of mercury, chromic acid, hydrogen sulphide and formaldehyde.
2. Repeated estimation of the percentage of carbon in a certain organic compound yielded the result, 38.42, 38.02 and 38.22 in three trials. What is the ‘spread’ of the above set of data?
3. State any two conditions for a good fractionation.
4. What is meant by partition chromatography?
5. If 0.4 g of NaOH is dissolved in water to give 500 ml solution what will be molarity of the solution?
6. Distinguish a primary standard from a secondary standard.
7. Define ‘Concentration solubility product’.
8. What are masking agents?
9. What are the properties measured in TG and DTG methods?
10. What do you understand by the term ‘reaction interval’ in thermal analysis?

PART – B

Answer any EIGHT questions                                                                 (8 x 5 = 40 marks)

11. Describe the calibration of a burette and a volumetric flask.
12. List out any five advantages of using a standard glass joint apparatus.
13. Assess the average deviation from the ‘mean’ and also from the ‘median’ of the percentage of chloride obtained in three trials, namely, 24.39, 24.19 and 24.36.
14. Describe ‘hot filtration’ and give its significance.
15. Outline the preparation and development of ‘plates’ for a TLC study.
16. Explain, briefly, the various steps involved in recrystallization of a solid.
17. What are metallochoromic indicators? Outline the principle and conditions for using such indicators.
18. Calculate the pH of the solution obtained by mixing 5.0 g of acetic acid and 7.5 g of sodium acetate and making the volume equal to 500 mL. Given: the dissociation constant of acetic acid is 1.75 x 10^-5 at 298 K.
19. Write an account of complexometric titrations.
20. Find out the solubility of magnesium hydroxide in g L^-1 if its solubility product is

1.20 x 10^-11 at 25^oC.  (Mg = 24, O=16, H=1).

21. Discuss the factors affecting solubility of precipitates.
22. Sketch and account for the DTA analysis of calcium oxalatemonohydrate.

 

PART – C

Answer any FOUR questions                                                                  (4 x 10 = 40 marks)

 

23. Write a detailed account of various kinds of determinate and indeterminate errors in analysis.
24. Discuss the principle, experimental technique and applications of ion-exchange

chromatography.

25. Write notes on: (i) reduced pressure distillation (ii) electron capture detector in GC.
26. Discuss the theory of acid-base indicators with two examples.
27. (i) Describe post precipitation. (ii) How is post precipitation different from coprecipitaion?

(iii) Mention any three requisites of a wash liquid.

28. Discuss the factors that influence a thermogram.

 

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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – CHEMISTRY

WD 18

FIFTH SEMESTER – April 2009

CH 5501 – ANALYTICAL CHEMISTRY

 

 

 

Date & Time: 17/04/2009 / 9:00 – 12:00 Dept. No.                                                  Max. : 100 Marks

 

 

 

PART – A

 

Answer ALL the questions                                                                                        (10 x 2 = 20 marks)

1. Define relative error.
2. How is antidote prepared?
3. Why is vaccum distillation needed for some liquids?
4. Define elution and eluant in chromatography.
5. Mention any two characteristics of a primary standard substance.
6. Define molarity
7. Differentiate equivalence point from end point.
8. How is solubility of sparingly soluble salt related to solubility product for AgCl?
9. State Beer-Lamberts law.
10. Draw the possible modes of vibrations for water molecule.

PART – B

Answer any EIGHT questions                                                                              (8×5=40 marks)

 

11. Define absolute error. The accepted value for the sets of data 25.40, 25.36, 25.26, 25.34 is 25.28.  Calculate the absolute error.
12. Write a note on Soxhlet extraction.
13. What are the steps involved in separation of mixture of components using TLC technique.
14. Mention principle and the different types of chromatography.
15. What are the different types of titrimetric analysis? Explain them with examples.
16. 20ml 0.1M CH COOH is titrated with 0.1 M NaOH calculate the pH at the equivalence point (Ka = 1.8 X 10^-5).
17. What is metal ion indicator? Give examples.
18. Explain co-precipitation and post precipitation with examples.
19. What is an adsorption indicator? Explain with an example.
20. Differentiate chromophore and auxochrome.
21. How is Beer-Lambert’s law veified? Explain them.
22. What are the factors affecting the absorption maximum in UV-visible spectroscopy?

 

PART – C

Answer any FOUR questions                                                                                  (4 x 10= 40 marks)

 

23. a) Define Mean, Median and Standard deviation                   (6)
24. b) Find out the mean and median for following data: 48.32, 48.36, 48.23, 48.11 and 48.38. (4)
25. a) Compare the following: distillation, fractional distillation and vaccum distillation.  Under

what conditions the above techniques are adopted for purification.                                         (7)

 

1. b) For a given volume of solvent, multiple extraction is more efficient than single extraction.

Why?                                                                                                                                              (3)

 

25. a) Explain the separation of a mixture by Gas chromatography.                    (7)
26. b) Write the different types of ion exchange resin used in ion-exchange chromatography.          (3)

 

26. a) What is meant by chelating agent? Give examples.                                                                  (2)
27. b) Explain the different types of EDTA titrations                                                                       (8)

 

27. a) How is silver ion determined by Volhard method?        (5)
28. b) Explain the factors affecting the solubility of a sparingly soluble salt.                                      (5)

 

28. Draw the block diagram of IR spectrometer and explain them. How IR absorption bands useful

in the identification of organic compounds?  Give examples.

 

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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

   B.Sc. DEGREE EXAMINATION – CHEMISTRY

FIRST SEMESTER – NOVEMBER 2010

CH 1502 – ANALYTICAL CHEMISTRY

 

 

 

Date : 10-11-10                     Dept. No.                                        Max. : 100 Marks

Time : 1:00 – 4:00

 

PART – A

 

Answer ALL questions.                                                                                               (10 x 2 = 20 marks)

 

1. What first aid will you do if a student spills phenol in his hands?
2. Write answers on the basis of significant figures for the following:
3. a) 7  +  0.08  +  2.9
4. b) 20  X  127/10.8
5. Name the types of adsorbents used in chromatography.
6. Define R_f.
7. Can we use phenolphthalein as indicator for the titration of Na₂CO₃ against HCl?
8. Define the term normality.
9. Mention the factors that influence precipitation.
10. What are complexometric titrations? Give one example.
11. Mention any two applications of TGA.
12. What do you understand by the term ‘reaction interval’ in thermal analysis?

 

PART – B

 

Answer any EIGHT questions.                                                                                      (8 x 5 = 40 marks)

 

11. List out the differences between accuracy and precision.
12. What are the advantages of a single pan balance over a double pan balance?
13. When is distillation done under reduced pressure? Draw a sketch of a distillation set.
14. Describe ‘hot filtration’ and give its significance.
15. Write a note on gas chromatography.
16. What are the conditions for a good primary standard?
17. Find out the solubility product of silver chloride. Its solubility in water is

9.6 X 10^-9 mol dm^-3.

18. Calculate the pH of a buffer solution containing 0.2M of acetic acid and 0.02 M of

sodium acetate. (Ka of acetic acid = 1.8 X 10^-5 at 25^oC)

19. Discuss one theory of acid-base indicators.
20. Explain adsorption indicators. Give examples.
21. Explain homogenous precipitation with an example.
22. Explain the thermal analysis of Ca(COO)₂.H₂O.

 

PART – C

 

Answer ANY FOUR questions.                                                                                   (4 x 10 = 40 marks)

 

23. a) Write a detailed outline about the types of errors.                         (5)

 

1. b) Find out the (i) mean (ii) median and  (iii) standard deviation for the

following data :  20.2, 19.3, 19.9, 21.5, 20.7.                                                                     (5)

 

24. a) Explain the Principle and applications of column chromatography.             (5)

 

1. b) Write briefly on ion exchange chromatography. (5)

 

25. a) When is Soxhlet extraction resorted to? Explain its principle with a diagram. (5)

 

1. b) Derive Henderson  equation for an acid buffer and mention its applications.                       (5)

 

26. a) How is Chloride ion in a solution estimated? (any one method)                         (5)

 

1.       b) Explain post precipitation.                                                                                                   (5)

 

27. a) Explain Von Weiman ratio.                         (5)

 

1.       b) What are the characteristics of metal-ion indicator?  Give an example.                      (5)

 

28. a) Discuss on the various components for the instrumentation of DTGA. (5)

 

1.       b)  Explain the factors that influence a thermogram.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – CHEMISTRY

FIRST SEMESTER – APRIL 2011

CH 1502/CH 5501 – ANALYTICAL CHEMISTRY

 

 

 

Date : 19-04-2011              Dept. No.                                                    Max. : 100 Marks

Time : 9:00 – 12:00

 

PART -A

Answer ALL the questions                                                                                          (10 x2 =20 marks)

 

1. Give the threshold limits of vapor concentration of mercury and formaldehyde.
2. How is ether handled in the laboratory?
3. A titration is repeated four times and the titre values are 10.1, 9.9, 10.0 and              10.2 ml. calculate the mean.
4. How is benzoic acid recrystallised?
5. What is R_f value?
6. Calculate the molarity when you dissolve 4.9 g of K₂Cr₂O₇ in 1000 ml of water.
7. Mention two adsorbents used in Column chromatography.
8. Mention any two indications used in the titration of a strong acid against a strong base?
9. What are adsorption indicators? Give an example.
10. Define co-precipitation.

PART – B

 

Answer any EIGHT questions                                                                                       (8 x 5 =40 marks)      

 

1. Describe the calibration of a pipette and standard flask.
2. Analysis of a sample of iron ore gave the following percentage values for the iron content 7.08,7.21.7.12,7.09,7.16, 7.14,7.07,7.14,7.18,7.11.Calculate the mean, standard deviation and coefficient of variation for the values.
3. Explain, briefly, the various steps involved in fractional distillation.
4. Discuss the preparation of chromatogram in Thin Layer chromatography.
5. What are the criteria for a primary standard? Give an example for primary and secondary standard.
6. Explain the principle of complexiometric titration with a suitable example.
7. Discuss the factors affecting solubility of precipitates.
8. Sketch the thermogram of calcium oxalate monohydrate.  Discuss the thermo gravimetric analysis technique.

 

 

1. Write briefly on ion-exchange chromatography.
2. What is normal error analysis curve? Give its significance.
3. Calculate the pH and the [H⁺] and [OH^–] concentrations of a 0.005 M solution of Ba (OH) ₂ in water at 25⁰C.
4. Calculate the molar solubility of Ag₂CrO₄ in water at 25⁰C at K_sp =9 x 10^-12.

 

PART – C

Answer any FOUR questions                                                                                   (4 x 10 =40 marks)      

 

1. Discuss the principle, experimental technique and instrumentation technique of Gas chromatography.
2. Explain in detail the types of errors.
3. Write briefly on a. Sublimation    b. Factors affecting R_f value.
4. Discuss the theory of acid- base indicators with suitable examples.
5. How is chloride determined by Volhard’s method?
6. a. Discuss the factors affecting TG and DTA thermograms.

1. Mention any three requisites of a good wash liquid in gravimeric analysis.

 

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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – CHEMISTRY

FIRST SEMESTER – APRIL 2012

CH 1502/CH 5501 – ANALYTICAL CHEMISTRY

 

 

 

Date : 28-04-2012              Dept. No.                                        Max. : 100 Marks

Time : 1:00 – 4:00

 

PART – A

 

Answer ALL the questions:                                                                                             (10×2=20)

 

1. Distinguish accuracy from precision.
2. Mention any two filtration techniques.
3. Name two drying agents.
4. Under what conditions distillation under reduced pressure is necessary?
5. Give any two advantages of thin layer chromatography over paper chromatography.
6. What is a buffer solution? Give an example.
7. Write two limitations of volumetric analysis.
8. Define solubility product.
9. Sketch the expected thermogram of calcium oxalate monohydrate in TGA.
10. What is gravimetric factor?

PART – B

 

Answer any EIGHT questions:                                                                                       (8X5=40)

 

11. Write the differences between co-precipitation and post-precipitation
12. How will you calibrate pipette and burette?
13. Find the number of significant figures in the following

(a)6.023X10²³  (b) 0.112  (c) 423.6            (d) 3.1X10¹⁰   (e) 0.00014

14. What are the first – aid procedures to be followed in the laboratory
15. Give the common methods employed to test the purity of the compound
16. Discuss the applications of R_f value.
17. Explain the precautions to be carried out during preparing a column.
18. Enlist the requirements for a good primary standard.
19. Methyl orange cannot be used for all acid-base titrations. Why?
20. Give the applications of adsorption indicators.
21. Discuss the factors that affect solubility.
22. Sketch the block diagram of DTA apparatus.

 

 

PART – C

 

Answer any FOUR questions:                                                                                        (4×10=40)

 

23. a) Discuss the factors that affect the thermogram.

 

1. b) Write the inferences that could be drawn from DTA.

 

24. Explain: a) Volhard’s method

 

1. b) Von Weiman ratio.

 

25. a) Deduce an expression connecting solubility and K_sp for Ag₂CrO₄.

 

1. b) What are metal ion indicators?

 

26. a) Write the significance of Henderson equations.

 

1. b) Give the definitions of (i) Normality          (ii) Formality             (iii) ppm      (iv) millimole.

 

27. Discuss the principle and applications of a) ion exchange chromatography
28. b) gas chromatography.

 

28. a) Explain the types of errors. (6)
29. b) Mention methods of minimizing errors. (4)

 

 

 

 

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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – CHEMISTRY

FIRST SEMESTER – NOVEMBER 2012

CH 1505/1502/5501 – ANALYTICAL CHEMISTRY

 

 

 

Date : 08/11/2012             Dept. No.                                        Max. : 100 Marks

Time : 1:00 – 4:00

 

PART –A

 

Answer ALL the questions:                                                                                     (10 x2 =20 marks)

 

1. Mention the antidote for CO and Pb²⁺ poisoning.
2. List the number of significant figures in the following numbers
3. i) 0.216 ii) 90.7
4. Give the advantages of TLC.
5. Define Sublimation.
6. What are primary standards? Give an example.
7. How many milliliters of 0.25 M solution of H₂SO₄ will react with 10 mL of 0.25 M solution of

NaOH?

7. What are adsorption indicators?
8. Define post precipitation.
9. What quantity is measured in TGA and in DTA?
10. Mention any two applications of TGA.

PART –B

 

Answer any EIGHT questions:                                                                          (8×5 =40 marks)

 

11. Calculate the mean and the standard deviation of the following set of analytical results:

15.67, 15.69 and 16.03g

12. How are poisonous chemicals stored in the laboratory?
13. Discuss the principle and applications of Paper chromatography.
14. How is the purity of a compound tested?
15. Discuss the different titrimetric methods.
16. Give the preparation of acid-base buffers.
17. Discuss the principle of Steam distillation.
18. Calculate the pH and pOH of a 1.00 x 10^-3M solution of acetic acid.
19. Explain the principle of complexiometric titration with a suitable example.
20. Sketch the thermogram of calcium oxalate monohydrate. Discuss the Thermo gravimetric

analysis technique.

21. Calculate the molar solubility of PbSO₄ if the solubility product is 1.6 x 10 ^-8.
22. What is von Weiman ratio? Define the terms in it.

 

PART -C

 

Answer any FOUR questions:                                                                                       (4×10 =40 marks)

 

23. Discuss the theory of acid- base indicators with suitable examples.
24. How is chloride determined by Volhard’s method?
25. What are absolute and relative errors? Give the methods of minimizing errors.
26. Explain the principle, technique and applications of ion-exchange chromatography.
27. Discuss the instrumentation of thermogravimetric analysis.
28. a) Give the properties and uses of drying agents.
29. b) What are metal ion indicators? Explain their characteristics.

 

 

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