JEE MAIN 2018 Sample Question Paper

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2 SET 1 Roll No. JEE MAIN 2018 Sample Question Paper CHEMISTRY (Theory) General Instructions (i) This test consists of 30 question. (ii) Each question is allotted 4 marks for correct response. (iii) Candidates will be awarded marks as stated above in instruction no. 2 for correct response of each question. 1 mark will be deducted for indicating incorrect response of each question. No deduction from the total score will be made if no response is indicated for an item in the answer sheet. (iv) There is only one correct response for each question. Filling up more than one response in any question will be treated as wrong response and marks for wrong response will be deducted according as per instructions. 1. The activation energy and enthalpy of chemisorption of oxygen on a metal surface is 37.3 kj mol -1 and 72.1 kj mol -1. At a certain pressure, the rate constant for chemisorption is s -1 at 318 K. What will be the value of the rate constant at 308 K? (1) s -1 (3) s -1 (2) s -1 (4) s -1 Page 2

3 2. Equivalent weight of KHC NaHC 2 4 in reaction with acidic KMn 4 is (M = molar mass) (1) M (2) M (3) M (4) M 3. The root mean square velocity of an ideal gas at constant pressure varies with density (d) as (1) d 2 (2) d (3) (4) 4. A monoatomic ideal gas undergoes a process in which the ratio of p to V at any instant is constant and equals to 1. What is the molar heat capacity of the gas? R (1) R (2) R (3) (4) 0 5. Given that E Fe Fe and E Fe Fe are 0.36V and 0.439V, respectively. The value of E Fe Fe Pt would be (1) ( ) V (2) ( ) V (3) [3(-0.36) +2(-0.439)] V (4) [3(-0.36) -2(-0.439)] V 6. Last line of Lyman series for H-atom has wavelength A 2 nd line of Balmer series has wavelength A then (1) (3) (2) (4) 7. The freezing point (in C) of solution containing 0.1 g of K 3 [Fe(CN) 6 ] (mol. wt. 329) in 100 g of water (K f = 1.86 K kg mol -1 ) is (1) (3) (2) (4) Page 3

4 8. How many litres of water must be added to 1 L of an aqueous solution of HCl with a ph of 1 to create an aqueous solution with ph of 2? (1) 0.1 L (2) 0.9 L (3) 2.0 L (4) 9.0 L 9. For the elementary reaction, M N, the rate of disappearance of M increases by a factor of 8 upon doubling the concentration of M. The order of the reaction with respect to M is (1) 4 (2) 3 (3) 2 (4) For the complete combustion of ethanol, C 2 H 5 H(l) (g) 2C 2 (g) + 3H 2 (l), the amount of heat produced as measured in bomb calorimeter, is kj mol -1 at 25 C. Assuming ideality the enthalpy of combustion, C H, for the reaction will be (R = J K -1 mol -1 ) (1) kj mol -1 (3) kj mol -1 (2) kj mol -1 (4) kj mol In a sample of h-atom electrons make transition from 5 th excited state to ground state, producing all possible types of photons, then number of lines in infrared region are (1) 4 (2) 5 (3) 6 (4) The species having tetrahedral shape is : (1) [PdCl 4 ] 2- (3) [Pd(CN) 4 ] 2- (2) [Ni(CN) 4 ] 2- (4) [NiCl 4 ] Graphite is a soft lubricant solid extremely difficult to melt. The reason for this anomalous behaviour is that graphite. (1) is a non-crystalline substance. (2) is an allotropic form of diamond (3) has molecules of variable molecular masses like polymers (4) has carbon atoms arranged in large plates of rings of strongly bound carbon atoms with weak inter plate bonds. Page 4

5 14. Identify the wrong statement in the following : (1) Chlorofluorocarbons are responsible for ozone layer depletion (2) Greenhouse effect is responsible for global warming (3) Acid rain is mostly because of oxides of nitrogen and sulphur (4) zone layer does not permit infrared radiation from the sun to reach the earth 15. In the standardisation of Na 2 S 2 3 using K 2 Cr 2 7 by iodometry, the equivalent weight of K 2 Cr 2 7 is (1) (molecular weight)/2 (2) (molecular weight)/6 (3) (molecular weight)/3 (4) same as molecular weight 16. Match List I with list II and select the correct answer using the code given below the lists : List (I) List (II) (a) Binding energy of 5 th excited state of Li 2+ sample (p) 10.2 V (b) I st excitation potential of H-atom (q) 3.4 ev (c) 2 nd excitation potential of He + ion (r) 13.6 ev (d) I.E. of H-atom (s) 48.4 V Code: (a) (b) (c) (d) (1) r p s q (2) s p q r (3) q r s p (4) q p s r 17. Which of the following graphs are correct for strong electrolyte AD and AB. (1) A m AB AD C (3) A m C AB AD (2) A m AB AD C (4) A m C AB AD 18. Potassium manganate (K 2 Mn 4 ) is formed when- (1) Cl 2 is passed into an aqueous solution of KMn 4 (2) Mn 2 is fused with KH (3) Formaldhyde reacts with KMn 4 in the presence of strong alkali (4) KMn 4 reacts with conc. H 2 S 4 Page 5

6 19. Give the correct order of initials T of F for following statements. Use T if statement is true and F if it false. (I) Number of S-S bonds in H 2 S n 6 are (n+1) (II) When F 2 reacts with water gives HF. 2 and 3 (III) LiN 3 and BaCl 2 compounds are used in fore works (IV) Be and Mg hydrides are ionic and polymeric (1) FTTF (2) FTTT (3) TFTT (4) TTFF 20. A substance responds to the following tests : (a) It gives a green precipitate with ammonia solution which dissolves in excess reagent forming deep blue solution. (b) It gives green precipitate with potassium cyanide solution which dissolves in excess reagent forming a yellow solution. (c) It gives a reddish-brown/brown-borax bead test in the oxidising flame. The substance is: (1) Sr 2+ salts (2) Ni 2+ salts (3) Mn 2+ salts (4) Zn 2+ salts g of an organic compound on heating with conc. HN 3 and silver nitrate in carius furnace gave 0.42 g of AgCl. Find the percentage of chlorine in the compound. (1) 52 (2) 64 (3) 89 (4) Test by which starch and cellulose can be distinguished from each other is : (1) reducing sugar test (2) analysis of products of hydrolysis (3) iodine test (4) Molisch test 23. The product P formed in the given reaction sequence is. C C 1. KH 3. ClCH N-H 2 CEt. 2. H 3 + P Page 6

7 (1) C NH-CH 2 -CEt. (3) NH 2 -CH 2 -C H C H C CH 2 CEt. (2) NH 2 -CH 2 -CC 2 H 5 (4) N-H C H CH 2 CEt. 24. After completion of the reactions (I and II), the organic compounds(s) in the reaction mixtures is : Reaction I: Reaction II: H 3 C CH 3 (1.0 mol) H 3 C CH 3 (1.0 mol) Br 2 (1.0 mol) aqueous/nah Br 2 (1.0 mol) CH 3 CH H 3 C P CH 2 Br H 3 C CBr 3 Q Br 3 C CBr 3 R BrH 2 C S CH 2 Br H 3 C CHBr 3 T Na U (1) Reaction I : P and Reaction II : P (2) Reaction I : U acetone and Reaction II : Q, acetone (3) Reaction I : T, U, acetone and Reaction II : P (4) Reaction I : R, acetone and Reaction II : S, acetone 25. The true statement about the major product of CH 3 -C-CH 2 -CH 2 -CH 2 -CH 2 -C-H in reaction with aq. NaH followed by heating is. (1) It gives yellow ppt with I 2 / - H (2) It gives silver mirror with Tollen s reagent (3) It shows stereoisomerism (4) It does not give yellow ppt with 2,4 DNP Page 7

8 26. CH 3 -CH-CH 3 PBr 3 A Mg/ether B CH 2 -CH 2 C H 2 D. D is: H (1) CH 3 -CH--CH 2 -CH 3 (2) CH 3 --CH-CH 2 CH 3 CH 3 (3) CH 3 -CH-CH 2 CH 2 H CH 3 (4) CH 3 -CH 2 -CH-CH 2 H CH 3 CH Match List I with List II and select the correct answer using the code given below the lists: List (I) (a) Gas dispersed in liquid (b) Liquid dispersed in gas (c) Liquid dispersed in solid (d) Liquid dispersed in liquid Codes: (a) (b) (c) (d) (1) q s r p (2) p s q r (3) s p q r (4) r q s p List (II) (p) Emulsion (q) Foam (r) Gel (s) Aerosol 28. Which of the following IUPAC name is incorrect? (1) 3-Ethylpenta-1, 4-diene (2) 2-Ethylhex-1-en-4-yne (3) 2-(2- Chloroethyl) pentanenitrile (4) 2, 2-Dichlorohexan-4-ol 29. In the reaction, product X is : CH 3 -C CH + H 2 H + /Hg 2+ (1) CH 3 CH 2 CH (2) CH 3 CH 2 CH (3) CH 3 - C(H) = CHH (4) CH 3 CCH 3 X Page 8

9 30. The major product of the following reaction is RCH 2 H H + (anhydrous) (1) a hemiacetal (2) an acetal (3) an ether (4) an ester Page 9