Chemistry Punjab PMS Paper I 2023

PUNJAB PUBLIC SERVICE COMMISSION
COMBINED COMPETITIVE EXAMINATION
FOR RECRUITMENT TO THE POSTS OF
PROVINCIAL MANAGEMENT SERVICE, ETC -2023
CASE NO. 1C2024
SUBJECT: CHEMISTRY (PAPER-II)
TIME ALLOWED: THREE HOURS MAXIMUM MARKS: 100
NOTE:
i. All the parts (if any) of each Question must be attempted at one place instead of at different places.
ii. Write Q. No. in the Answer Book in accordance with Q. No. in the Q. Paper.
iii. No Page/Space be left blank between the answers. All the blank pages of Answer Book must be crossed.
iv. Extra attempt of any question or any part of the question will not be considered.
NOTE: Attempt any FIVE Questions in all. Attempt in Urdu or English.
Q.No.1 a) Explain the rules of resonance with examples. Discuss the contribution of different canonical forms. (20 Marks)
Q.No.2 a) Describe various types of electronic transition and types of absorption bands which arise as a result of electronic transition in compounds.
b) Explain the difference between:
(1) Red shift and blue shift (2) Transmittance and absorbance
(3) Chromophore and auxochrome (4) Allowed and forbidden transition
(12+8=20 Marks)
Q.No.3 a) How will you synthesize ethyl phenyl ketone from each of the following compounds?
(1) Benzene (2) Benzoyl chloride (3) Benzoic acid
(4) Benzaldehyde (5) Benzonitryl.
b) What do you know about condensation reaction? Describe two types of condensation reactions shown by aldehydes. (10+10=20 Marks)
Q.No.4 a) How will you prepare following compounds starting from benzene in two step mechanism?
(1) p-Chloro nitrobenzene (2) m-Chloro nitro benzene (3) Ethyl cyclohexane
(4) n-Propyl benzene (5) m-Dinitro benzene
b) Why activating group direct in coming electrophile to ortho and para and deactivating group to meta position. (10+10=20 Marks)
Q.No.5 a) What are carbohydrates? Discuss metabolism of carbohydrates.
b) What are Lipids? How you can classify them. Discuss their importance.
(10+10=20 Marks)
Q.No.6 a) What is TLC? Explain its mechanism. Discuss its applications.
b) Compare gas chromatography with liquid chromatography. (14+6=20 Marks)
Q.No.7 a) Discuss the application of Dyes.
b) What are pigments? How they can be manufactured? Give some examples.
(8+12=20 Marks)
Q.No.8 a) Explain the conformational analysis. On what factors conformational energy depends?
b) Define optical activity. What are chiral compounds ? How chirality is determined by using polarimeter?
(10+10=20 Marks)