BCHCT-133 EM 2026 SOLVED ASSIGNMENT

Description

Tutor Marked Assignment
CHEMICAL ENERGETICS, EQUILIBRIA AND
FUNCTIONAL ORGANIC CHEMISTRY I
Core Course in Chemistry
Course Code: BCHCT-133
Assignment Code: BCHCT-133/TMA/2026

ENGLISH MEDIUM

COMPLETE SOLUTIONS

 

PART A: CHEMICAL ENERGETICS AND EQUILIBRIA

1. List the differences between thermodynamically reversible and irreversible processes with the suitable examples. (5)
2. Derive a relation between temperature and volume for an adiabatic process. 1.00 mole of helium gas at temperature of 100 ℃ undergoes reversible adiabatic expansion from an initial volume of 5 𝑑𝑚3 to 30 𝑑𝑚3. Calculate the final temperature of the gas by assuming that the helium behaves ideally and has 𝐶𝑉,𝑚 = 12.47 𝐽𝐾−1𝑚𝑜𝑙−1. (5)
3. Two molecule of ∝ −𝐷 −glucose condense in enzyme catalyzed reaction to give a molecule of disaccharide, maltose. Calculate the enthalpy of the reaction. The enthalpies of combustion of crystalline ∝ −𝐷 −glucose and maltose at 25 ℃ are −2809.1 𝑘𝐽𝑚𝑜𝑙−1 and 5645.5 𝑘𝐽𝑚𝑜𝑙−1, respectively. (5)
4. (a) Differentiate between enthalpy driven and entropy driven reactions with the help of suitable examples. (2)

(b) What is the chemical potential? Explain it with its significance.

5. In the equilibrium mixture of three ideal gases A, B, C 𝐴 (𝑔) ⇋ 𝐵 (𝑔) + 𝐶 (𝑔) obtained by dissociation of 𝐴 to the extent of 20 % at a total pressure of 1.0 𝑎𝑡𝑚, what are the partial pressure of 𝐴, 𝐵 and 𝐶.
6. Consider the following reaction � �2 +3 𝐻2 ⇋2𝑁𝐻3

In which direction, towards reactants and towards products, does the reaction shift if the equilibrium is stressed by each change? (i) 𝐻2 is added (ii) 𝑁𝐻3 is added (iii) 𝑁𝐻3 is removed. (5)

7. (a) Which factor affect the degree of ionization of weak electrolyte. Explain in brief. (2)

(b) Calculate the pH of 0.010 𝑀 aqueous solution of NaOH at 25 ℃. (3)

8. (a) Explain the effect of common ion on the ionization equilibrium of weak acids with the help of a suitable example.

(b) The pH of an aqueous solution of lactic acid 𝐶𝐻3𝐶𝐻(𝑂𝐻)𝐶𝑂𝑂𝐻-a weak acid was found to be 2.7. Calculate the concentration of solution if 𝐾𝑎 for lactic acid is 1.4 × 10−4 . (3)

9. Arrange the following salt of magnesium in the order of increasing solubilities. � �𝑔𝐹2, 𝑀𝑔𝐶𝑂3,𝑀𝑔3(𝑃𝑂4)2 [Given: 𝐾𝑠𝑝(𝑀𝑔𝐹2) = 3.7 × 10−8; 𝐾𝑠𝑝(𝑀𝑔𝐹2) = 3.5 × 10−8; and � �𝑠𝑝(𝑀𝑔𝐹2) = 1.0×10−25 at 25 ℃.] (5)
10. A 1.00 𝑚𝑜𝑙 sample of 𝑁𝑂𝐶𝑙 was placed in a 2.00 𝐿 reactor and heated to 227 °𝐶 until the system reached equilibrium. The contents of the reactor were then analyzed and found to contain 0.056 𝑚𝑜𝑙 of 𝐶𝑙2. Calculate 𝐾 at this temperature. The equation for the decomposition of 𝑁𝑂𝐶𝑙 to 𝑁𝑂 and 𝐶𝑙2 is as follows: 2𝑁𝑂𝐶𝑙(𝑔) → 2𝑁𝑂(𝑔) + 𝐶𝑙2(𝑔) PART B: FUNCTIONAL GROUP ORGANIC CHEMISTRY-I
11. (a) What is Hückel rule? Define this with suitable example.

(b) How would you prepare benzene from ethyne? Write its mechanism.

12. (a) What are the limitations of Friedel-Crafts alkylation reactions?

(b) Write the product of the following reactions. (i) (ii) (iii) (

13. (a) Write the mechanism of chlorination of methyl benzene. (2)

(b) Predict the reactant of the following reaction: (i) (ii) (iii) (1×3) 14. (a) Arrange the following molecules in order of increasing boiling points. Give reason for this trend: 𝐶𝐻𝐶𝑙3, 𝐶𝐻2𝐶𝑙2,𝐶𝐻3𝐶𝑙,𝐶𝐶𝑙4 (2)

(b) Complete the following reactions

15. (a) Which of the following compounds undergo 𝑆𝑁1/𝑆𝑁2 reaction? Explain. (i) Benzyl chloride; (ii) Chlorobenzene; (iii) Chloroethene; (iv) Chloroethyne

(b) Write the product and mechanism of the following reaction. (3)

16. Complete the following reaction and write its mechanism:
17. Write the mechanism of the formation of salicylic acid from phenol.
18. (a) Give two important features of the crown ethers.

(b) Write product for the following reactions

19. How will you prepare primary, secondary and tertiary alcohols from same Grignard reagent?
20. How will you bring about following conversions?
21. a) Benzaldehyde to cinnamaldehyde
22. b) Benzaldehyde to cinnamic acid
23. c) Acetophenone to dypnone
24. d) Acetophenone to 1,2,3-triphenylbenzene
25. e) Acetophenone to 1-Phenyl-1,3-butanedione