PUNJAB PUBLIC SERVICE COMMISSION
COMBINED COMPETITIVE EXAMINATION
FOR RECRUITMENT TO THE POSTS OF PROVINCIAL MANAGEMENT SERVICE-2021
SUBJECT: CHEMISTRY (PAPER-1)
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. All Questions Carry Equal Marks. Attempt in English or Urdu.
Q No. 1: a). Define entropy. Describe entropy changes and conclusions for reversible and irreversible process. (2+4+4=10 Marks)
b). Explain the significance of Gibbs free energy as useful work. (10 Marks)
Q No. 2: a). What is hybridization of orbitals? Give comparison of Sigma and Pi bonds. Explain Sp2 hybridization. (2+4+4=10 Marks)
b). Write down the main points of Molecular Orbital Theory (MOT) and explain the structure of HF molecule. (5+5=10 Marks)
Q No. 3: a). What is molar conductance? How are the conductance / resistance measured? (2+8=10 Marks)
b). Define electrode potential. Explain standard hydrogen electrode. (2+8=10 Marks)
Q No. 4: a). What is Pauli Exclusion Principle? How does it helps and effect in distribution of electrons in an atom? (3+7=10 Marks)
b). Derive Schrodinger wave equation for calculating the Laplacian operator. (10 Marks)
Q No. 5: a). What are the main postulates of Werner’s theory and explain structure of CoCl3.6NH3. (7+3=10 Marks)
b). What are chelates and give classification? Give examples of the formation of chelates. (2+2+6=10 Marks)
Q No. 6: a). What is radioactive decay? Describe the decay of Beta (β+ , β-) particles. (2+8=10 Marks)
b). Differentiate nuclear fission and nuclear fusion process. (10 Marks)
Q No. 7: a). What is the composition of cement? Describe the Wet process for the manufacture of Cement. (10 Marks)
b). Define fertilizers and explain the classification of fertilizers. (2+8=10 Marks)
Q No. 8: a). What are pollutants? How air pollution can be controlled? (10 Marks)
b). Write a note of any one: (10 Marks)
(i) Green house effect (ii) Water pollution
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