Course Code: BCHCT-135
Assignment Code: BCHCT-135/TMA/2023
Maximum Marks: 100

PART-(A)

1. (a) What are ideal solutions? Give two examples of such solutions.

(b) Draw and explain the vapour pressure curves for an ideal solution.

2. Draw and explain the mutual solubility curve for the phenol-water system.

3. (a) How do the impurities Affect the CST values? Explain.

(b) Explain the stability of different phases of a pure substance in terms of chemical potential versus temperature curves.

4. Define any five of the following terms:
(i) Phase
(ii) Azeotropes
(iii) Congruent melting
(iv) Concentration cell
(v) Conductometric titration
(vi) Galvanic cells

5. (a) What is the criterion for phase equilibrium for a heterogeneous system at constant pressure and temperature?

(b) Define components in the context of phase rule. Calculate the number of components for the sublimation equilibrium of \(\mathrm{NH} 4 \mathrm{Cl}\) assuming that \(\mathrm{NH}_3(\mathrm{~g})\) and \(\mathrm{HCl}(\mathrm{g})\) are produced from the sublimation of \(\mathrm{NH}_4 \mathrm{Cl}(s)\) only.

6. (a) What is the triple point for a one component system? What is the degrees of freedom at the triple point?

(b) Draw and explain the phase diagram for a simple eutectic system and give an industrial application for the same.

7. (a) Define molar conductivity and give its significance.

(b) In a conductivity cell, the two platinum electrodes, each having an area of \(2 \mathrm{~cm}^2\) are \(1 \mathrm{~cm}\) apart. Using this cell the resistance of a \(0.1 \mathrm{M}\) solution of acetic acid is found to be \(470 \Omega\). Calculate the molar conductivity of the solution.

8. (a) List the requirements for an electrolyte to be indicator electrolyte in the moving boundary method for the determination of transference numbers’

(b) In the determination of transference numbers of \(\mathrm{HCl}\) by moving boundary method a \(0.10 \mathrm{M}\) solution of \(\mathrm{HCl}\) was taken in a cell having uniform area of cross section of \(1.0 \mathrm{~cm}^2\). At the end of experiment the boundary moved by \(10.3 \mathrm{~cm}\) and \(0.132 \mathrm{~g}\) of silver was deposited on the cathode of silver coulometer. Calculate the transference numbers of ions of \(\mathrm{HCl}\).

9. (a) Differentiate between reversible and irreversible cells.

(b) Write the cell diagram for a galvanic cell in which the following reaction takes place.
\[
\mathrm{Sn}(\mathrm{s})+2 \mathrm{Ag}^{+}(\mathrm{aq}) \rightarrow \mathrm{Sn}^{2+}(\mathrm{aq})+2 \mathrm{Ag}(\mathrm{s})
\]
Assume that potassium nitrate is used as electrolyte in the salt bridge and the concentrations of tin ions and silver ions are \(c_1\) and \(c_2\) respectively.

10. (a) Define electrolysis. Name the gases evolved in the electrolysis of brine.

(b) Define liquid junction potential and describe its development.

PART-(B)

11. Discuss the mechanism of Hell-Vohlard-Zelinsky reaction.

12. Write the mechanism and the products formed for the following reactions:

13. (a) Give the IUPAC names of the following compounds:

(b) Briefly explain the following reactions:
(i) Hofmann rearrangement
(ii) Schmidt rearrangement

14. (a) How will you prepare the following compounds? Give reactions.
(i) 4-methylbiphenyl
(ii) 4-hydroxyazobenzene
(iii) butter yellow dye

(b) How will you convert 4-bronobenzenmine to 4-bromobenzenol?

15. (a) Discuss the nitrosation reaction of primary amines.

(b) Discuss the nitration reaction of aniline. How would you account for the formation of different products?

16. (a) What is electrophoresis? Briefly explain. Also give its importance.

(b) What BOC-group? Which reagent is used to introduce this group?

17. How will you synthesise valine using Gabriel phthalimide synthesis?

18. Discuss the secondary structure of peptides.

19. (a) Briefly explain the phenyl osazone formation by monosaccharides.

(b) Why do D-(+)-glucose and D-(+)-mannose give the same osazone?

20. (a) What are polysaccharides? Give examples.

(b) Briefly explain the structure aspects of starch.