This document contains an unsolved chemistry practice paper from 1984 for the IIT JEE entrance exam. It has 5 sections with multiple choice, true/false, fill in the blank, and matching questions testing concepts in chemistry. The questions cover topics like radioactive decay, hybridization of orbitals, acid-base chemistry, organic reactions, gas laws, and more. The document provides a chemistry review and test to help students prepare for the competitive Indian engineering entrance exam.

1. IIT JEE - Past papers CHEMISTRY- UNSOLVED PAPER – I984

2. SECTION – I Single Correct Answer Type This section contains 20 multiple choice questions. Each question has four choices (A), (B), (C) and (D) out of which ONLY ONE is correct.

3. 01 Problem The radiations from a naturally occurring radioactive substance, as seen after deflection by a magnetic field in one direction, are: Definitely alpha rays Definitely beta rays Both alpha and beta rays Either alpha or beta rays

4. Problem 02 The increasing order (lowest first) for the values of e/m (charge/mass) for electron e, proton p, neutron n and alpha particles is: a. b. N, p, e, c. N, p, , e d. N, p, e

5. Problem 03 On hybridization of one s and one p orbitals we get: Two mutually perpendicular orbitals Two orbitals at 1800 Four orbitals directed tetrahedrally Three orbitals in a plane

6. Problem 04 Correct set of four quantum numbers for the valence (outermost) electron of rubidium (Z = 37) is: 5, 0, 0, 5, 1, 0 5, 1, 1, 6, 0, 0,

7. Problem 05 Which electronic level would allow the hydrogen atom to absorb a photon but not to emit a photon? 3s 2p 3p 1s

8. Problem 06 Equal masses of methane and hydrogen are mixed in an empty container at . The fraction of the total pressure exerted by hydrogen is: 1/2 8/19 1/9 16/17

9. Problem 07 A liquid is in equilibrium with its vapor at its boiling point . On the average, the molecules in the two phases have equal: Inter-molecular forces Potential energy Kinetic energy Temperature

10. Problem 08 Pure ammonia is placed in vessel at a temperature where its dissociation constant ( ) is appreciable. At equilibrium: does not change significantly with pressure Does not change with pressure Concentration of NH3 does not change with pressure Concentration of hydrogen is less than that of nitrogen

11. Problem 09 Zinc-copper couple that can be used as a reducing agent is obtained by: Mixing zinc dust and copper gauze Coated zinc with copper Coating copper with zinc Welding together zinc and copper wires

12. Problem 10 A solution containing one mole per liter each of is electrolyzed using inert electrodes, standard electrode potentials in volts (reduction potentials) are: With increases voltage, the sequence of deposition of metals on the cathode will be: Ag, Hg, Cu, Mg Mg, Cu, Hg, Ag Ag, Hg, Cu Cu, Hg, Ag

13. Problem 11 The electric charge for electrode deposition of one gram equivalent of a substance is: One ampere for one second 96,500 coulombs per second One ampere for one hour Charge on one mole of electrons

14. Problem 12 The hydration energy of is greater than that of: a. b. c. d.

15. Problem 13 certain buffer solution contains equal concentration of and HX. The for is . The pH of the buffer is: 4 7 10 d. 14

16. Problem 14 A certain weak acid has a dissociation constant of 1.0 X The equilibrium constant for its reaction with a strange base is: 1.0 X 1.0 X 1.0 X 1.0 X

17. Problem 15 The IUPAC name of the compound having the formula is: 3,3, -trimethyl-1-propene 1, 1, 1-trimethyl-2-propene 3,3-dimethyl-1-butene 2,2-dimethyl-3-butene

18. Problem 16 Baeyer’s reagent is : Alkaline permanganate solution Acidified permanganate solution Neutral permanganate solution Aqueous bromine solution

19. Problem 17 An industrial method of preparation of methanol is: Catalyst reduction of carbon monoxide in presence of By reacting methane with steam at 900 0C with a nickel catalyst By reducing formaldehyde with lithium aluminum hydride By reacting formaldehyde with aqueous sodium hydroxide solution

20. Problem 18 When phenol is treated with excess bromine water, it gives: M-bromophenol o-and p-bromophenol 2, 4-dibromophenol 2, 4, 6-tribromophenol

21. Problem 19 Carbylamines test is performed in alcoholic KOH by heating a mixture of: Chloroform and silver powder Trihalogenated methane and a primary amine An alkyl halide and a primary amine An alkyl cyanide and a primary amine

22. Problem 20 Chlorobenzene can be prepared by reacting aniline with: Hydrochloric acid Cuprous chloride Chlorine in the presence of anhydrous aluminum chloride Nitrous acid followed by heating with cuprous chloride.

23. SECTION – II true or false State whether the following statements are true or false

24. 01 Problem In aqueous solution chlorine is a stronger oxidizing agent than fluorine.

25. Problem 02 Silver chlorine is more soluble in very concentrated sodium chloride than in pure water.

26. Problem 03 If equilibrium constant for the reaction is K, then for the backward reaction the equilibrium constant is 1/K.

27. Problem 04 The H-N-H bond angle in NH3 is greater than the H – As –H bond angle is .

28. Problem 05 When a liquid and its vapor are in equilibrium and the pressure is suddenly decreased, cooling occurs.

31. Problem 02 An element that can exist as a positive ion in acidic solution and as a negative ion in basic solution is said to be __________

32. Problem 03 The acidity of phenol is due to the _________ of its anion.

33. Problem 04 The acidity of phenol is due to the _________ of its anion.

34. Problem 05 for an ideal gas is _______

35. SECTION – IV Each the following statements is true only under some specific conditions. Write the condition for each sub- questions in not more than two sentences.( Example : Answer to (vii) is “gases are assumed ideal and P and T are Constant “.

36. 01 Problem Two volatile and miscible liquids can be separated by fractional distillation into pure components

37. Problem 02 The heat energy absorbed by a gas is H.

38. Problem 03 Metals can be recovered from their ores by chemical methods.

39. Problem 04 High purity metals can be obtained by zone refining method.

40. Problem 05 2-Methylpropene can be converted into isobutyl bromide by hydrogen bromide.

41. Problem 06 Ethyne and its derivatives will give white precipitate with ammoniacal silver nitrate solution.

42. Problem 07 Equal volumes of gases contain equal number of moles.

43. SECTION – V Match the following

44. 01 Problem A B C Asbestos molecular sieve air pollutant Fluorocarbons paramagnetic carcinogen Lithium metal refrigeration f luorescent paint Nitric oxide reducing agent electron donor Zeolites semiconductor i on exchanger Zinc oxide silicates of (Ca + Mg) propellent

45. FOR SOLUTION VISIT WWW.VASISTA.NET