This document contains a 45 question chemistry exam from 1994 with multiple choice answers for each question. The questions cover a wide range of chemistry topics including organic chemistry reactions, properties of acids and bases, transition metals, thermodynamics, kinetics, and other general chemistry concepts.

1. AIPMT–PAST PAPERS
CHEMISTRY- UNSOLVED PAPER - 1994

2. 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

3. 01 Problem
Which one of the following statements is not true?
a. Ampicillin is a natural antibiotic
b. Aspirin is both analgesic and antipyretic
c. Sulphadiazine is a synthetic antibacterial drug
d. Some disinfectants can be used as antiseptics.

4. 02 Problem
Which one of the following order is wrong, with respect to the property
indicated?
a. Benzoic acid > phenol > cyclohexanol (acid strength )
b. Aniline > cyclohexylamine > benzamide (basic strength )
c. Formic acid > acetic acid > propanoic acid (acid strength )
d. Fluroacetic acid > chloroacetic acid > bromoacetic acid (acid strength ).

5. 03 Problem
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
a. Methyl chloride
b. Monochloro acetic acid
c. Chloral
d. Chloroform.

6. 04 Problem
An acyl halide is formed when PCl5 reacts with an
a. Amide
b. Ester
c. Acid
d. Alcohol.

7. 05 Problem
Which of the following compound will undergo self aldol condensation in
the presence of cold dilute alkali?
a. CH C – CHO
b. CH2 = CH – CHO
c. C6H6CHO
d. CH3CH2CHO.

8. 06 Problem
Diazo – coupling is useful to prepare some
a. Dyes
b. Vitamins
c. Pesticides
d. Proteins.

9. 07 Problem
On heating glycerol with conc. H2SO4, a compound is obtained which has
bad odour. The compound is
a. Acrolein
b. Formic acid
c. Allyl alcohol
d. Glycerol sulphate.

10. 08 Problem
The most suitable method of the separation of a 1 : 1 mixture of ortho-
and para-nitrophenols is
a. Crystallization
b. Chromatography
c. Distillation
d. Sublimation.

11. 09 Problem
Which of the following compounds will give positive test with Tollen’s
reagent?
a. Acetic acid
b. Acetone
c. Acetamide
d. Acetaldehyde.

12. 10 Problem
By the action of enzymes, the rate of biochemical reaction
a. Does not change
b. Increases
c. Decreases
d. Either (a) or (c).

13. 11 Problem
Reaction of t-butyl bromide with sodium methoxide produces
a. Sodium t-butoxide
b. t-butyl methyl ether
c. isobutene
d. Isobutylene.

14. 12 Problem
The reactive species in the nitration of benzene is
a. NO3
b. NHO3
c. NO 2
d. NO 2

15. 13 Problem
Grignard reagent is prepared by the reaction between
a. Magnesium and alkane
b. Magnesium and aromatic hydrocarbon
c. Zinc and alkyl halide
d. Magnesium and alkyl halide.

16. 14 Problem
Which of the following statement concerning lanthanides elements is
false?
a. All lanthanides are highly dense metals
b. More characteristic oxidation state of lanthanides elements is +3
c. Lanthanides are separated from one another by ion exchange method
d. ionic radii of trivalent lanthanides steadily increases with increase in
the atomic number.

17. 15 Problem
The action of nitrous acid on an aliphatic primary amine, gives
a. Secondary amine
b. Nitro alkane
c. Alcohol
d. Alkyl nitrite.

18. 16 Problem
One of the following which does not observe the anti-Markownikoff’s
addition of HBr, is
a. Pent-2-ene
b. Propene
c. But-2-ene
d. But-1-ene.

19. 17 Problem
The compound which does not react with sodium, is
a. CH3COOH
b. CH3-CHOH-CH3
c. C2H5OH
d. CH3-O-CH3.

20. 18 Problem
Which of the following ligands is expected to bidentate?
a. CH3NH2
b. CH3C N
2
c. Br 4
d. C2O

21. 19 Problem
Method used for obtaining highly pure silicon, used as a semiconductor
material, is
a. Crystallization
b. Zone refining
c. Oxidation
d. Electro-chemical.

22. 20 Problem
Which one of the following statements is not correct?
a. Mercury (II) iodide dissolves in excess of potassium iodide solution
b. Tin (IV) chloride is made by dissolving tin solution in concentrated
hydrochloric acid
c. Zinc dissolves in sodium hydroxides solution
d. Carbon monoxide reduces iron (III) oxide to iron.

23. 21 Problem
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
a. Availability of low lying Assertion (A) :- orbitals in silicon
b. Large size of silicon
c. More electropositive nature of silicon
d. Both (b) and (c).

24. 22 Problem
Which of the following transition element shows the highest oxidation
state?
a. V
b. Cr
c. Mn
d. Fe.

25. 23 Problem
Which of the following oxides of nitrogen is paramagnetic ?
a. NO2
b. N2O3
c. N2O
d. N2O5.

26. 24 Problem
To protect iron against corrosion, the most durable metal plating on it, is
a. Copper plating
b. Zinc plating
c. Nickel plating
d. Tin plating.

27. 25 Problem
Which of the following statements about H3BO3 is not correct ?
a. It has a layer structure in which planar BO3 units are joined by
hydrogen bonds
b. It does not act as proton donor but acts as a Lewis acid by accepting
hydroxyl ion
c. It is a strong tribasic acid
d. It is prepared by acidifying an aqueous solution of borax.

28. 26 Problem
Which of the following displaces Br2 from an aqueous solution containing
bromide ions?
a. I2
b. I 3
c. Cl2
d. Cl-.

29. 27 Problem
Ionic solids, with Scotty defects, contain in their structure
a. Cation vacancies only
b. Cation vacancies and interstitial cations
c. Equal number of cation and anion vacancies
d. Anion vacancies and interstitial anions.

30. 28 Problem
Which pair of substances gives same gaseous product, when these react
with water?
a. K and KO2
b. Ba and BaO2
c. Ca and CaH2
d. Na and Na2O2.

31. 29 Problem
Which of the following salt has the same value of vant’s Hoff factor I
as that of K3[Fe(CN)6]?
a. Na2SO4
b. Al(NO3)3
c. Al2(SO4)3
d. NaCl

32. 30 Problem
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?
a. Ba2+
b. Mg2+
c. Na+
d. Li+.

33. 31 Problem
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
a. rate = k[A][B]3
b. rate = k [A]2[B]2
c. rate = k[B]3
d. rate = k[B]4

34. 32 Problem
Which one of the following is not is electronic with O2-?
a. TT+
b. Na+
c. N3-
d. F-.

35. 33 Problem
For the adsorption of a gas on a solid, the plot of log (x/m) versus log P is
linear with slope equal to
a. n
b. 1/n
c. k
d. log k.

36. 34 Problem
Which of the following molecules has the highest bond order?
a. O2-
b. O2
c. O2+
d. O22-

37. 35 Problem
Following reaction occurring in an automobile
2C8 H18 g 25O2 g 16CO2 g 18H2O g The sign of H, S and G would be
a. -. +, +
b. + , + , -
c. +, - , +
d. -, +, -.

38. 36 Problem
At 250C, the highest osmotic pressure is exhibited by 0.1 M solution of
a. Glucose
b. Urea
c. CaCl2
d. KCl.

39. 37 Problem
How many grams of CH3OH should be added to water to prepare 150 ml
solution of 2 M CH3OH ?
a. 9.6 X 103
b. 2.4 X 103
c. 9.6
d. 2.4.

40. 38 Problem
Which substance is serving as a reducing agent in the following reaction ?
14 H Cr2O72 3Ni 7 H 2O 3Ni 2
a. H+
b. H2O
c. Ni.
d. Cr2O2-7

41. 39 Problem
Which of the following molecule does not possess a permanent dipole
moment?
a. CS2
b. SO3
c. H2S
d. SO2.

42. 40 Problem
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
a. 32 minutes
b. 64 minutes
c. 8 minutes
d. 12 minutes.

43. 41 Problem
The formula for calcium chlorite is
a. CaClO2
b. Ca(ClO2)2
c. Ca(ClO4)2
d. Ca(ClO3)2.

44. 42 Problem
In a radioactive decay, an emitted electron comes from
a. Outermost orbit of the atom
b. Orbit having principal quantum number one
c. Nucleus of the atom
d. Inner orbital of the atom.

45. 43 Problem
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
a. 2 x 1025
b. 1 x 1025
c. 4 x 1025
d. 3 x 1025.

46. 44 Problem
Which one of the following is most soluble?
a. Bi2S3 (Ksp = 1 x 10-70)
b. Ag2S (Ksp = 6 x 10-51)
c. Cus (Ksp = 8 x 10-37)
d. MnS(Ksp = 7 x 10-16)

47. 45 Problem
The temperature of a gas is raised from 270C to 9270C. The root mean
square speed of the gas
a. Remains same
b. Gets 927 times
27
c. Gets halved
d. Gets doubled.

48. 46 Problem
For which of the following sets of four quantum numbers, an electron will
have the highest energy ?
n l m s
a. 3 2 1 +1/2
b. 4 2 -1 +1/2
c. 4 1 0 -1/2
d. 5 0 0 -1/2.

49. 47 Problem
The oxidation state of 1 in H4IO6- is
a. + 1
b. -1
c. + 7
d. + 5.

50. 48 Problem
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?
a. C
b. D.
c. A
d. B

51. 49 Problem
At 800C, distilled water has [H3O+] concentration equal to 1 x 10-6 mole/litre.
O P F 1, The value of Kw at this temperature will be
a. 1 x 10-12
b. 1 x 10-15
c. 1 x 10-6
d. 1 x 10-9

52. 50 Problem
The total number of valence electrons in 4.2 gm of N ion is ( is the
Avogadro’s number )
a. 2.1
b. 4.2
c. 1.6
d. 3.2

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