aipmt–Past papers CHEMISTRY- UNSOLVED PAPER - 1994
SECTION – I (Total Marks : 50) Single Correct Answer Type There are five parts in this question. Four choices are given for each part and one of them is correct. Indicate you choice of the correct answer for each part in your answer-book by writing the letter (a), (b), (c) or (d) whichever is appropriate
01 Problem Which one of the following statements is not true? Ampicillin is a natural antibiotic Aspirin is both analgesic and antipyretic Sulphadiazine is a synthetic antibacterial drug Some disinfectants can be used as antiseptics.
Problem 02 Which one of the following order is wrong, with respect to the property indicated? Benzoic acid > phenol > cyclohexanol (acid strength ) Aniline > cyclohexylamine > benzamide (basic strength ) Formic acid > acetic acid > propanoic acid (acid strength ) Fluroacetic acid > chloroacetic acid > bromoacetic acid (acid strength ).
Problem 03 Compound A has a molecular formula C2Cl3OH. It reduces Fehling’s solution and on oxidation, it gives a monocarboxylic acid B. If A is obtained by the action of chlorine on ethyl alcohol, then compound A is Methyl chloride Monochloro acetic acid Chloral Chloroform.
Problem 04 An acyl halide is formed when PCl5 reacts with an Amide Ester Acid Alcohol.
Problem 05 Which of the following compound will undergo self aldol condensation in the presence of cold dilute alkali? CH C – CHO CH2 = CH – CHO C6H6CHO CH3CH2CHO.
Problem 06 Diazo – coupling is useful to prepare some Dyes Vitamins Pesticides Proteins.
Problem 07 On heating glycerol with conc. H2SO4, a compound is obtained which has bad odour. The compound is Acrolein Formic acid Allyl alcohol Glycerol sulphate.
Problem 08 The most suitable method of the separation of a 1 : 1 mixture of ortho-and para-nitrophenols is Crystallization Chromatography Distillation Sublimation.
Problem 09 Which of the following compounds will give positive test with Tollen’s reagent? Acetic acid Acetone Acetamide Acetaldehyde.
Problem 10 By the action of enzymes, the rate of biochemical reaction Does not change Increases Decreases Either (a) or (c).
Problem 11 Reaction of t-butyl bromide with sodium methoxide produces Sodium t-butoxide t-butyl methyl ether isobutene Isobutylene.
Problem 12 The reactive species in the nitration of benzene is NO3 NHO3 NO NO
Problem 13 Grignard reagent is prepared by the reaction between Magnesium and alkane Magnesium and aromatic hydrocarbon Zinc and alkyl halide Magnesium and alkyl halide.
Problem 14 Which of the following statement concerning lanthanides elements is false? All lanthanides are highly dense metals More characteristic oxidation state of lanthanides elements is +3 Lanthanides are separated from one another by ion exchange method ionic radii of trivalent lanthanides steadily increases with increase in the atomic number.
Problem 15 The action of nitrous acid on an aliphatic primary amine, gives
Problem 16 One of the following which does not observe the anti-Markownikoff’s addition of HBr, is Pent-2-ene Propene But-2-ene But-1-ene.
Problem 17 The compound which does not react with sodium, is CH3COOH CH3-CHOH-CH3 C2H5OH CH3-O-CH3.
Problem 18 Which of the following ligands is expected to bidentate? CH3NH2 CH3C N Br C2O
Problem 19 Method used for obtaining highly pure silicon, used as a semiconductor material, is Crystallization Zone refining Oxidation Electro-chemical.
Problem 20 Which one of the following statements is not correct? Mercury (II) iodide dissolves in excess of potassium iodide solution Tin (IV) chloride is made by dissolving tin solution in concentrated hydrochloric acid Zinc dissolves in sodium hydroxides solution Carbon monoxide reduces iron (III) oxide to iron.
Problem 21 Carbon and silicon belong to (IV) group. The maximum coordination number of carbon in commonly occurring compounds is 4, whereas that of silicon is 6, This is due to Availability of low lying Assertion (A) :- orbitals in silicon Large size of silicon More electropositive nature of silicon Both (b) and (c).
Problem 22 Which of the following transition element shows the highest oxidation state? V Cr Mn Fe.
Problem 23 Which of the following oxides of nitrogen is paramagnetic ? NO2 N2O3 N2O N2O5.
Problem 24 To protect iron against corrosion, the most durable metal plating on it, is Copper plating Zinc plating Nickel plating Tin plating.
Problem 25 Which of the following statements about H3BO3 is not correct ? It has a layer structure in which planar BO3 units are joined by hydrogen bonds It does not act as proton donor but acts as a Lewis acid by accepting hydroxyl ion It is a strong tribasic acid It is prepared by acidifying an aqueous solution of borax.
Problem 26 Which of the following displaces Br2 from an aqueous solution containing bromide ions? I2 I Cl2 Cl-.
Problem 27 Ionic solids, with Scotty defects, contain in their structure Cation vacancies only Cation vacancies and interstitial cations Equal number of cation and anion vacancies Anion vacancies and interstitial anions.
Problem 28 Which pair of substances gives same gaseous product, when these react with water? K and KO2 Ba and BaO2 Ca and CaH2 Na and Na2O2.
Problem 29 Which of the following salt has the same value of vant’s Hoff factor I as that of K3[Fe(CN)6]? Na2SO4 Al(NO3)3 Al2(SO4)3 NaCl
Problem 30 Standard reduction potentials at 250C of Li+|Li,Ba2+|Ba, Na+|Na and Mg2+|Mg are – 3.05, -2.90,-2.71 and –2.37 volt respectively. Which one of the following is the strongest oxidizing agent? Ba2+ Mg2+ Na+ Li+.
Problem 31 The data for the reaction A + B -> C, is Exp. [A]0 [B]0 Initial rate 1 0.012 0.035 0.10 2 0.024 0.070 0.80 3 0.024 0.035 0.10 4 0.012 0.070 0.80 the rate law corresponds to the above data is rate = k[A][B]3 rate = k [A]2[B]2 rate = k[B]3 rate = k[B]4
Problem 32 Which one of the following is not is electronic with O2-? TT+ Na+ N3- F-.
Problem 33 For the adsorption of a gas on a solid, the plot of log (x/m) versus log P is linear with slope equal to n 1/n k log k.
Problem 34 Which of the following molecules has the highest bond order? O2- O2 O2+ O22-
Problem 35 Following reaction occurring in an automobile The sign of H, S and G would be -. +, + + , + , - +, - , + -, +, -.
Problem 36 At 250C, the highest osmotic pressure is exhibited by 0.1 M solution of Glucose Urea CaCl2 KCl.
Problem 37 How many grams of CH3OH should be added to water to prepare 150 ml solution of 2 M CH3OH ? 9.6 X 103 2.4 X 103 9.6 2.4.
Problem 38 Which substance is serving as a reducing agent in the following reaction ? H+ H2O Ni. Cr2O2-7
Problem 39 Which of the following molecule does not possess a permanent dipole moment? CS2 SO3 H2S SO2.
Problem 40 50 ml of hydrogen diffuses out through a small hole of a vessel, in 20 minutes. The time taken by 40 ml of oxygen to diffuse out is 32 minutes 64 minutes 8 minutes 12 minutes.
Problem 41 The formula for calcium chlorite is CaClO2 Ca(ClO2)2 Ca(ClO4)2 Ca(ClO3)2.
Problem 42 In a radioactive decay, an emitted electron comes from Outermost orbit of the atom Orbit having principal quantum number one Nucleus of the atom Inner orbital of the atom.
Problem 43 The number of atoms is 100 g of an FCC crystal with density Assertion (A) : = 10 g/cm3 and cell edge equal to 100 pm, is equal to 2 x 1025 1 x 1025 4 x 1025 3 x 1025.
Problem 44 Which one of the following is most soluble? Bi2S3 (Ksp = 1 x 10-70) Ag2S (Ksp = 6 x 10-51) Cus (Ksp = 8 x 10-37) MnS(Ksp = 7 x 10-16)
Problem 45 The temperature of a gas is raised from 270C to 9270C. The root mean square speed of the gas Remains same Gets times Gets halved Gets doubled.
Problem 46 For which of the following sets of four quantum numbers, an electron will have the highest energy ? n l m s 3 2 1 +1/2 4 2 -1 +1/2 4 1 0 -1/2 5 0 0 -1/2.
Problem 47 The oxidation state of 1 in H4IO6- is + 1 -1 + 7 + 5.
Problem 48 The table shown below gives the bond dissociation energies (Ediss) for single covalent bonds of carbon (C) atoms with element A, B, C and D. which element has the smallest atoms? C D. A B
Problem 49 At 800C, distilled water has [H3O+] concentration equal to 1 x 10-6 mole/litre. The value of Kwat this temperature will be 1 x 10-12 1 x 10-15 1 x 10-6 1 x 10-9
Problem 50 The total number of valence electrons in 4.2 gm of N ion is ( is the Avogadro’s number ) 2.1 4.2 1.6 3.2