Chemistry PPSC Lecturer MCQS Solved.. From Past papers for Test Preparation

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14) Diamond is:
(a) Good conductor of electricity (b) Bad conductor of electricity
(c) Bad conductor on heating  (d) Good conductor on heating
15) Carbon monoxide is poisonous gas because it:
(a) replaces oxygen from lungs (b) forms carboxy haemoglobin
(c) Forms carbon dioxide with oxygen (d) has a sweet smell
16. Rust is:
(a) FeO + Fe(OH)2 (b) Fe2O3 + Fe(OH)2 (c) Fe2O3 (d) Fe2O3 + Fe(OH)3
17) Calcium Carbide reacts with water to give:
(a) Methane (b) Ethylene (c) Acetylene (d) Ethane
18. Which of the following substituent deactivates benzene ring and is o, p-directing?
(a) __ NH2 (b) __ Cl (c) __ OCH3 (d) __ OH
19) Which of the following is most readily nitrated?
(a) Toluene  (b) Benzaldehyde (c) Nitrobenzene  (d) Benzoic Acid
20) Ketones can be prepared by reaction of Grignard reagent with:
(a) Acid Amides (b) Acid Chloride (c ) Carboxylic Acid (d) Epoxides
21) Which of the following statements about the order of reaction is true?
(a) The order of a reaction can only be determined by experiment.
(b) A second order reaction is also bimolecular
(c) The order of reaction must be a positive integer
(d) The order of reaction increases with increasing temperature.
22 Polysaccharides yield many monosaccharides on:
(a) Hydration (b) Oxidation (c) Reduction (d) Hydrolysis
23) Which of the following is not aromatic?
(a) Benzene  (b) cyclooctatetraene (c) Pyridine (d) Phenol
24) Which of the following is most basic?
(a) H2O (b) NH3 (c) CH3NH2 (d) CH3OH
25) Which of the following has lowest pH?
(a) CH3COOH (b) CF3COOH (c) ClCH2COOH (d) Cl3C COOH
26) The equilibrium of two readily interconvertible isomers is called:
(a) Stereoisomerism (b) Metamerism (c) Tautomerism (d) Polymorphism
27) Which of the following compounds exhibit geometrical isomerism?
(a) 1-Pentene (b) 2-Pentene (c) 2-methyl –2-Pentene (d) 2-methyl –2-Butene
28) Which of the following gives a tertiary alcohol when treated with Grignard reagent:
(a) HCHO (b) CH3CHO (c) C3H5CHO (d) CH3COCH3
29) Which of the following tests is not used to identify aldehydes?
(a) Tollen’s test (b) Benedict solution test (c) Fehling solution test (d) Ammonia test
30) Which is incorrect about alkaloids?
(a) Naturally Occuring (b) Possess a hetrocyclic ring
(c) Exhibit biological action  (d) acidic in nature
31) Which of the followings will not give iodoform test:
(a) Acetone (b) Ethylacohol (c) Benzaldehyde (d) Acetaldehyde
32) The reaction of aniline with bromine water gives:
(a) o-bromoaniline (b) p-bromoaniline (c) 2,4-dibromoaniline (d) 2,4,6-tribromoaniline
33) The reaction of tripalmitin, with sodium hydroxide is called:
(a) Hydrolysis (b) Saponification (c) Esterification (d) Combustion
34) Which one is not Petrochemical?
(a) Napthalene (b) Mineral Oil (c) Wax (d) Table Salt
35) Chemical adsorption:
(a) is exothermic (b) is irreversible (c) takes place at high temp. (d) All of these
36) The most commonly used absorbent for chromatographic separation of organic compound is:
(a) Activated charcoal (b) Fuller’s Earth (c) Alumina (d) Silica gel
37) Grignard reagent is:
(a) Organo Zinc halide (b) Organo cadmium bromide
(c) n-Butyl Lithium (d) Organo Magnesium halide
38)  Which one of the following is not a petrochemical.
(a) Cumene (b) Paraffin (c) Aluminum Chloride (d) Epoxy resin
39)  The term syndiotactic is related to which one of the following?
(a) Synthetic detergents (b) Table Salt (c) Paraffin (d) Polyprophylene
40  Which one of the following is used as an Antibiotic?
(a) Patulin (b) Insulin (c) Soserine (d) Trypsin
41)  Heroin is diacetate of:
(a) Papaverine (b) Morphine(c) Codeine (d) Thebaine
42)  A reaction that practically is given by all organic compounds.
(a) Elimination (b) Friedel-Craft ecylation (c) Combustion (d) Rearrangement
43)  Which functional group is present in polyester shirt?
(a) Lactam (b) Acid Chloride (c) Ether (d) Ester
(xviii) Which statement is true for Halogen (Halo-group)?
(a) Activating and O, p–directing (b) Activating and m–directing
(c) Deactivating and O, p–directing (d) None of these.
(44)  Which one of the following can be synthesized from Aryl Diazonium Salt?
(a) Furfural (b) Carbylamine (c) Biphenyl (d) THF
(45  The Methyl group in Methyl Magnesium Iodide can act as:
(a) CH3Radical (b) CH3Carbonium ion (c) CH3Carbanion (d) Can react with a base
46)  Nylon is a copolymer of:
(a) Urea and Formaldehyde (b) Phenol and Formaldehyde
(c) Hexamethylenediamine and adipic acid (d) Vinyl Chloride and Vinylalcohol
(47)  Which of the following would react with one mole of Grignard’sreagent to yield a ketone?
(a)  R   R RCON ′ ′ ′ (b)  R RCONH ′(c) RCONH2(d) RCOOH
48)  Glyceraldehyde has one ofthe following properties:
(a) One asymmetric carbon atom(b) Two asymmetric carbon atoms
(c) A meso compound (d) Four asymmetric carbon atoms
49  The ant
ifreeze compound ethylene glycol has the formula:
(a) C2H5OH (b) CH3OH (c) C2H4(OH)2(d) C3H5(OH)3
50  Distillation is the best method for separating the two substances in which of the following:
(a) Water and salt dissolved
(b) water and a substance which does not dissolve in it
(c) Two liquids that have different boiling points
(d) Two solids that have different melting points.

Chemistry Mcqs For CSS & PSC Exams

(i) The geometry associated with sp3d 2 hybridization is:
(a) Octahedral (b) Tetrahedral (c) Trigonal planar (d) Trigonal biplanar
(ii) Which of the following molecules has a dipole movement?
(a) CH4 (b) CO2 (c) H2 O (d) CCl 4
(iii) Which of the following represents the shape of NH 3 molecule?
(a) Trigonal planar (b) Angular (c) Trigonal Pyramidal (d) Tetrahedral
(iv) Which of the following is the largest ion?
(a) Li  (b) Cs  (c) Rb  (d) Na 
(v) Which of the following represent different isotopes of the same element?
1. 12 protons, 11 neutrons, 12 electrons
2. 11 protons, 12 neutrons, 11 electrons
3. 10 protons, 12 neutrons, 12 electrons
4. 11 protons, 12 neutrons, 10 electrons
5. 12 protons, 12 neutrons, 12 electrons
(a) 1 and 5 (b) 2 and 4 (c) 2, 3, 4 and 5 (d) None of these
(vi) Which of the following represents the correct number of particles in 79 2 
34 Se ?
(a) 34 protons, 79 neutrons, 2 electrons (b) 34 protons, 45 neutrons, 32 electrons
(c) 34 protons, 45 neutrons, 2 electrons (d) 34 protons, 45 neutrons, 36 electrons
(vii) Which one of the following is correct equation for the reaction of chlorine with water?
(a)
2Cl + H 2 O2HCl +
2
1
O2
(b) Cl 2 + 2H 2 O 2HCl + H 2 O2
(c) Cl 2 + 3H 2 OHClO3 + 5HCl (d) Cl 2 + H 2 O HCl + HOCl

(ix) When Pt and Co are electrically connected, which one is corroded:
(a) Pt (b) Co (c) Both of these (d) None of these
(x) For the reaction (Zn + Cu 2  Zn 2 +Cu), which of the following statements is correct?
(a) Zn is dissolved and Cu is deposited (b) Cu is reduced and Zn is exidized
(c) Cu is the cathode and Zn the anode (d) All statements are correct
(xi) What is the pH of 0.0001 M NaOH solution?
(a) 4 (b) 10 (c) 5 (d) 14
(xii) What is the pH of 1.0 x 10 3M HCl solution?
(a) 10 (b) 30 (c) 3 (d) 0.3
(xiii) Which of the following is the correct equilibrium expression for the reaction
[N 2 (g) + 3H 2(g) 2 ( )] 3 NH g ?
(a) [ 3 2NH ][N 2 + 3H 2 ] (b) [2NH 3 ] / [N 2 ][3H 2 ]
(c) [NH 3 ] 2 / [N 2 ][H 2 ] 3 (d) [NH 3 ] 2 / [N 2 ]+[H 2 ] 3
(xiv) Which of the following best describes how a catalyst works?
(a) It changes the potential energies of the reactants and products.
(b) It decreases the temperature of the reaction which leads to a faster rate.
(c) It lowers the activation energy for the reaction by providing a different reaction mechanism.
(d) It raises the activation energy for the reaction which produces a faster rate.
(xv) Which of the following will not act as Lewis acid;
(a) AlCl 3
(b) BF3
(c) FeBr 3
(d) CCl 4
(xvi) Which of the following is the strongest acid?
(a) HF (b) HCl (c) HBr (d) HI
(xvii) Which of the following could be used for cathodic protection:
(a) Al (b) Cd (c) Cu (d) None of these
(xviii) Hybridization of XeF 4 is:
(a) sp 3 d (b) sp 2 d 2 (c) sp 3 d 2 (d) sp 3
(xix) Which of the following will increase the rate of the reaction?
(a) Decreased temperature and increased concentration of reactants
(b) Decreased temperature and decreased concentration of reactants
(c) Increased temperature and decreased concentration of reactants
(d) Increased temperature and increased concentration of reactants
(xx) Silicones are polymeric substances with linkage:
(a) Si – S – Si (b) Si – O – Si (c) Si (CH 3 ) 4
(d) O = Si = O