PPSC 2015 chemistry paper
The PPSC Lecturer Chemistry Paper of 2015 was a competitive exam conducted by the Punjab Public Service Commission (PPSC) for selecting qualified candidates for the role of Chemistry Lecturer in government colleges across Punjab. The exam covered a wide range of topics in chemistry, testing candidates’ knowledge in areas such as:
- General Chemistry Concepts: Fundamental concepts across physical, organic, and inorganic chemistry.
- Stoichiometry: Calculation-based questions involving chemical equations, molar relationships, and reaction yields.
- Organic Chemistry: Questions related to the structure, properties, and reactions of organic compounds.
- Inorganic Chemistry: Focused on the periodic table, coordination chemistry, and inorganic reaction mechanisms.
- Physical Chemistry: Topics such as thermodynamics, kinetics, and chemical equilibrium.
- Analytical Chemistry: Techniques and methodologies for chemical analysis and data interpretation.
1. Enzymes are…. in nature
a. protein
b. fatty acid
c. vitamins
d. none
2. Enzymes belong to which class of compounds:
a. polysaccharides
b. polypeptides
c. poly nitro heterocyclic componds
d. hydrocarbons
3. Helical structure of proteins is stabilized by
a. peptide bonds
b. dipeptide bonds
c. hydrogen bonds
d. van der waals forces
4. The function of enzyme in living system is to :
a. transport oxygen
b. provide immunity
c. catalyze biochemical reactions
d. provide energy
5. Which of the following vitamins deficiency cause night blindness:
a. A
b. B
c. C
d. D
6. Which of following is an example of Zwitter ion :
a. alanine
b. glycine hydrochloride
c. both a and b
d. none
7. What does IR spectroscopy allow us to determine:
a. The kinds of bonds in a compound
b. The number of carbons in a compound
c. The molecular formula of a compound
d. C-H framework of a compound
8. Marsh gas contain:
a. CO2
b. H2S
c. CH4
d. C2H4
9. Which of the solvent is best to use when taking IR spectrum:
a. methanol
b. CCl4
c. water
d. ethanol
10. A strong peak between 1700cm-1 and 1760cm-1 in an IR spectrum is most likely to indicate
a. Alkene
b. Alkyne
c. Saturated group
d. Carbonyl group
11. What type of radiation is used in NMR spectroscopy:
a. visible light
b. UV light
c. radio waves
d. IR rays
12. Experimental evidence for the existence of atomic nucleus comes from
a. Milikan’s oil droplet method
b. Atomic absorption spectroscopy
c. Magnetic bending of cathode rays
d. Alpha scattering by a thin metal foil
13 Which of the following is false in case of electron:
a. it is a particle
b. it emit energy while moving in orbits
c. it has a wave property
d. its motion is effected by magnetic field
14. Which of the following is whole number:
a. atomic weight
b. atomic number
c. atomic radii
d. equivalent weight
15. Electronic configuration of M2+ ion is 2,8,14 and its atomic weight is 56amu. The number of neutrons in the nucleus is:
a. 30
b. 32
c. 34
d. 42
16. The ratio between neutron present in C and Si w.r.t atomic mass 12 and 28 is :
a. 3:7
b. 7:3
c. 3:4
d. 6:28
17. The stability of the nucleus mainly depend on the number of:
a. protons and neutrons
b. neutrons and electrons
c. protons and electrons
d. all of these
18. The difference between the total mass of the particle present and real mass of an atom is called:
a. mass
b. energy
c. mass defect
d. binding energy
19. A certain mass of a gas occupies a volume of 2L at STP. Keeping the pressure constant at what temperature would the gas occupy a volume of 4L
a. 273oC
b. 546oC
c. 50oC
d. 100oC
20. The difference between crystalloid and colloid is
a. solubility
b. diffusion
c. particle size
d. chemical composition
21. A liquid is found to scatter a beam of light but leaves no residue when passed through filter paper.The liquid can be described as:
a. true solution
b. colloidal solution
c. suspension
d. oil
22. At equilibrium which of the following solution is not effected by pressure:
a. 1/2N2 + 1/2O2 <………>NO
b. PCl5 <……..> PCl3 + Cl2
c. SO2Cl2 <………> SO2 + Cl2
d. none of these
23. In the lime kiln, the reversible reaction CaCO3 <…..> CaO + CO2 proceeds to completion because:
a. CO2 escapes
b. CaO is removed
c. of low temperature
d. of high pressure
24. In which of the following cases does the reaction go farthest to completion:
a. K =102
b. K = 1
c. K =10
d. K = 10-2
25. Preparation of ice cream is based on the principle of:
a. exchange of solvent
b. peptization
c. coagulation
d. excessive cooling
26. Random motion of colloidal particles in the dispersion medium refers to:
a. coagulation
b. adsorption
c. brownian movement
d. none
27. In the hydrogentaion of oils the catalyst used is:
a. Ni
b. Pt
c. Fe
d. Cu
28. When dispersion medium is gas, the colloidal system is
a. aerosol
b. alcosol
c. benzosol
d. hydrosol
29. The unit of equilibrium constant Kc for the reaction N2 + H2 <……> 2NH3 will bw:
a. L2mol2
b. L2mol-2
c. molL-1
d. no unit
30. The term active mass of a substance is used to denote the number of :
a. grams per liter
b. molecules per liter
c. grams atom per liter
d. gram molecules per liter
31. For a reversible reaction to reach an equilibrium state, the reaction is said to be carried out:
a. glass vessel
b. iron vessel
c. open vessel
d. closed vessel
32. According to Le-Chatliers principle, adding heat to a solid and liquid in equilibrium will cause the:
a. amount of solid to decrease
b. amount of liquid to decrease
c. temp to rise
d. temp to fall
33. The equation that describes the quantitaive relationship between pressure and amount of gas absorbed at constant temperature is called:
a. freundklch equation
b. langmuir equation
c. BET equation
d. none
34. Which of the following adsorption takes place at low temp:
a. physical adsoption
b. chemical adsoption
c. sorption
d. desorption
35. Among the following reactions, the faster one is :
a. burning of coal
b. conversion of monoclinic S to rhombic S
c. rusting of iron
d. precipitation of AgCl by mixing AgNO3 and NaCl solution
36. Colloidal particles are:
a. positively charged
b. negatively charged
c. either positively or negatively charged
d. neutral
37. Molecularity of a reaction :
a. always a whole number
b. cannot be less than 2
c. can have a fractional value
d. can be zero
38. Which one of the following compounds is depleting the ozone umbrella
a. chloroform
b. clorofloro carbon
c. bromomethane
d. none
39. The term -dx/dt in the rate expression tell:
a. change in concentration of reactant with time
b. instantaneous rate of reaction
c. average rate of reaction
d. none
40. The rate of a chemical reaction:
a. increase as the reaction proceeds
b. decreases as the reaction proceeds
c. both a and b
d. remain constant as the reaction proceeds
41. Inversion of cane sugar in aqueous solution to glucose and fructose is an example of:
a. fast reaction
b. slow reaction
c. spontaneous reaction
d. instantaneous reaction
42. Point out the correct statement:
a. rate law is an experimental fact whereas the law of mass action is a theoretical proposal
b. rate is always different from the expression of law of mass action
c. rate law is more informative than the law of mass action for the development of mechanism
d. order of the reaction is equal to the sum of power of concentration term in rate law
44. Under a given set of experimental conditions with increase in concentration of reactants, the rate of chemical reaction:
a. increases
b. decreases
c. remains constant
d. first increase then decrease
45. A catalyst increase the rate of reaction by:
a. decrease activation energy
b. increase activation energy
c. reacting with reactants
d. reacting with products
46. Mark the correct statement in case of reversible reaction:
a. catalyst catalyze the forward reaction
b. catalyst catalyze the backward reaction
c. catalyst catalyze the forward reaction and backward reaction to same extent
d. catalyst increase the forward but decrease the backward reactions’s rate
47. Order of a reaction :
a. cannot be determined experimentally
b. can have a fraction value
c. can be written from the balanced chemical equation
d. depends upon the stichiometric co-efficient of reactants and products
48. Which of the following aqueous solution will conduct an electric current:
a. sugar
b. glycerol
c. water
d. HCl
49. Which element has highest electrical conductivity:
a. silver
b. gold
c. copper
d. aluminium
50. Pure water doesnot conduct electricity because it is:
a. neutral
b. really decomposed
c. almost unionized
d. completely ionized
51. Which quantities are not required to calculate enthalpy change of formation of gaseous sodium ion
a. entahlpy change of atomization of sodium
b. first ionization of sodium
c. ehthalphy change of formation of sodium
d. none
52. Molten KCl conduct electricity due to presence of
a. free ions
b. free electrons
c. free molecules
d. atoms of potassium and chloride
53. The temperature of system decrease in an:
a. adiabatic expansion
b. adiabatic compression
c. isothermal expansion
d. isothermal compression
54. An isothermal process is one in which:
a. delta E = 0
b. delta T= 0
c. delta V = 0
d. delta H = 0
55. The system in which there is no exchange of heat between system and surrounding is called:
a. isobaric process
b. isochoric process
c. adiabatic process
d. isothermal process
56. Entrophy decrease in :
a. melting of ice
b. rusting of iron
c. vaporization of camphor
d. crystallization of sucrose from solution
57. Entropy of universe is always:
a. increasing
b. decreasing
c. zero
d. constant
58. Process of evaporation of liquid is accompained by:
a. decrease in enthalpy
b. increase in enthalpy
c. no change in free entropy
d. no change in free energy
59. According to Lowry Bronsted concept base is a substance which act as:
a. electron acceptor
b. electron donor
c. proton donor
d. proton acceptor
60. The weakest lewis base is:
a. H–
b. OH–
c. Cl–
d. HCO–
61. According to lewis concept base is a substance which:
a. accepts a proton
b. donates a proton
c. accepts a lone pair of electron
d. donates a lone pair of electron
62. Which one of the folowing least resembles an ideal gas:
a. ammonia
b. helium
c. hydrogen
d. trichloromethane
63. Compound X doesnot conduct electricity when in liquid state, when added to water produces a solution that readily conducts electricity.What could X be:
a. MgCl2
b. SiCl4
c. PCl3
d. none
64. A compound that does not give a positive test in Lassaigne’s test for N is:
a. phenyl hydrazine
b. glycine
c. urea
d. hydrazine
65. A gas decolorize alkaline KMnO4 solution but does not precipiate with ammonical AgNO3 solution is a:
a. ethylene
b. ethane
c. methane
d. acetylene
66. Which conclusion can be drawn from the reaction 3Cl2 + 6NaOH ……> NaClO3 + 5NaCl +3H2O
a. the oxidation state of chlorine in one of the product is +3
b. chlorine undergo disproportionation reaction
c. sodium hydroxide act as a reducing agent
d. none
67. Modern cars are fitted with catalytic convertors. These remove CO, unburn HC and oxides of nitrogen from exhaust gases.Which of these pollutant gases are removed by oxidation:
a. CO
b. NO
c. HC
d. none
68. For a compound to be purified by steam distillation:
a. impurities must be non volatile
b. liquid must be immisicble with water
c. molecular weight of compound is expected to be high
d. all are correct
70. Point out the false statement . Strong oxidizing character is favored by:
a. low ionization energy of halogen atom
b. high electrin affinity of halogen atom
c. high hydration energy of gaseous halide ion
d. low heat of dissociation of molecular hydrogen
71. Oxidizing action increases in the following order:
a. I<Br<F<Cl
b. I>Br>Cl>F
c. I<Br<Cl<F
d. Br<I<Cl<F
72. Complex with multidendate ligands is called:
a. chelates
b. covalent complex
c. coordination complex
d. none
73. EAN of Ni in Ni(CO)4:
a. 38
b. 18
c. 36
d. 54
74. Benzene molecule contains:
a. six sp2 hybrid carbons
b. six sp3 hybrid carbons
c. three sp3 hybrid carbons
d. three sp2 hybrid carbons
75. Molecular compounds in which individual components loose their identity are called:
a. complex compounds
b. lattice compounds
c. simple salts
d. all of these
76. Benzene is converted into toulene by:
a. Grignard reaction
b. Perkin reaction
c. Friedal craft reaction
d. Wurtz reaction
77. The cyclic formula for benzene was proposed by:
a. Kekule
b. Dewar
c. Beyers
d. Landberg
78. Which one of the following acid can be used as catalyst in Friedal craft reaction:
a. ALCl3
b. HNO3
c. BeCl2
d. ZnCl2
79. Alkyl groups are ortho para directing because:
a. inductive effect
b. resonance effect
c. resonance effect through hyper conjugation
d. all of these
80. Six carbon of benezene are proposed by:
a. one type
b. two type
c. three type
d. four type
81. Which one og the following is not explosive:
a. tri nitrobenzene
b. trinitro toulene
c. nitra glycerine
d. o-aminotoulene
82. Which of the following is least soluble in water:
a. ethanol
b.phenol
c. benzene
d. benzoic acid
83. The chlorine atom attached to benzene ring is:
a. para directing
b. otho directing
c. otho and para directing and activating
d. otho and para directing and deactivating
84. The oxides and chlorides of an element X are separately mixed with water. The two resulting solutions have the same effect on litmus. what is element X:
a. Na
b. Mg
c. Al
d. P
85. Which compound is the product of hydrolysis of CH3CO2C3H7 by boiling aq NAOH:
a. CH3OH
b. C3H7OH
c. C3H7COOH
d. none
86. Which alcohol maybe oxidized to a product which reacts with 2,4-dinitro phenylhydrazine reagent but not a fehling reagent:
a. butan-1-ol
b. butan-2-ol
c. 2-methylpropan-2-ol
d. 2-methylpropan-1-ol
87. Fluorescein, tatrazine, rhodamine and chromotrope are example of:
a. acid base indicators
b. adsorption indicators
c. mixed indicators
d. extractive indicators
88. The indicator that should not be added in a volumetric flask in which the titration carried out:
a. self indicator
b. internal indicator
c. external indicator
d. mixed indicator
89. Phenolphthalein is colorless in acidic medium because it has:
a. benzenoid structure
b. quinoid structure
c. dissociated structure
d. undissociated structure
90. In the manufacturing of sulphuric acid platinized asbestos is used as a catalyst, it is an example of:
a. promotor
b. autocatalyst
c. heterogenous catalysis
d. homogenous catalysis
91. The first attempt to classify elements was made by:
a. Dobereiner
b. Newland
c. Mendeleeve
d. Lother meyer
92. Theory of heterogenous catalysis is based on the phenomena of:
a. absorption
b. adsorption
c. sorption
d. dissoctaion
93. Molecular orbitals are filled with electrons according to:
a. aufbau principle
b. hund’s rule
c. pauli’s exclusion rule
d. all
94. Which of the following phenomenon will occur when two atoms of the element having same spin of electrons approach for bonding:
a. orbital overlap will not occur
b. bonding will not occur
c. both a and b
d. none
95. The oxidation no of P in KH2PO4 is
a. +1
b. +3
c. -3
d. +5
96. A mixture in heating with conc.H2SO4 and MnO2 liberates brown vapors of :
a. NO2
b. Br2
c. Cl2
d. I2
97. Resonating forms of a molecule can :
a. be separated
b. never be separated
c. both can be possble depending on conditions
d. none
98. Solids can be separated from liquid by:
a. distillation
b. separating funnel
c. sublimation
d. filteration
99. Periodic table was discovered by:
a. mosele
b. henry
c. joerge
d. none
100. Baking soda formula is:
a. Na2CO3
b. NaOH
c. NaHCO3
d. none