( ) PART A CHEMISTRY. Li 6 1s 1s 2s. Li 7 1s 1s 2s 2s 4 3. Li + 2 is more stable than Li 2 because Li 2 has more numbers of antibonding electrons.

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Alfred York
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1 JEE (MAIN)-13-CMP - PART A CHEMISTRY 1. An unknown alcohol is treated with the Lucas reagent to determine whether the alcohol is primary, secondary or tertiary. Which alcohol reacts fastest and by what mechanism: (1) tertiary alcohol by S N 1 () secondary alcohol by S N (3) tertiary alcohol by S N (4) secondary alcohol by S N 1 Reaction proceeds through carbocation formation as 3 carbocation is highly stable, hence reaction proceeds through S N 1 with 3 alcohol.. The first ionization potential of Na is 5.1 ev. The value of electron gain enthalpy of Na + will be: (1) 5.1 ev (3) 1. ev (3) +.55 ev (4).55 ev H =+ 5.1eV + Na Na + e, here the backward reaction releases same amount of energy and known as H= 5.1eV Electron gain enthalpy. 3. Stability of the species Li, Li and Li + increases in the order of: (1) + Li Li Li (3) + Li Li Li + < < (3) Li < Li < Li + < < (4) Li < Li < Li * ( ) = σ σ σ Li 6 1s 1s s B.. = 4 = 1 + ( ) * 1 Li 5 = σ1s σ1s σ s 3 B.. = =.5 * * ( ) = σ σ σ σ 1 Li 7 1s 1s s s 4 3 B.. = =.5 Li + is more stable than Li because Li has more numbers of antibonding electrons. 4. The molarity of a solution obtained by mixing 75 ml of.5 (M) H with 5 ml of (M)H will be: (1) 1. M () M (3).975 M (4).875 M M 1 V 1 + M V = MV M1V1 + M V M = = V 1 M = Which of the following is the wrong statement? (1) 3 molecule is bent () zone is violet-black in solid state (3) zone is diamagnetic gas (4) N and N are not isoelectronic Sol. (All the options are correct statements) (1) Correct, as is bent. FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

2 JEE (MAIN)-13-CMP-3 () Correct, as ozone is violet-black solid. (3) Correct, as ozone is diamagnetic. (4) Correct, as N = 3 electrons and N = 4 electron hence are not isoelectronic. All options are correct statements. 6. Four successive members of the first row transition elements are listed below with atomic numbers. Which E M /M one of them is expected to have the highest E value? (1) Mn(Z = 5) () Fe(Z = 6) (3) Co(Z = 7) (4) Cr(Z = 4) E E E = Mn /Mn = Fe /Fe = Co /Co 3 Cr /Cr 1.57 V.77 V 1.97 V + + =.41 V 7. A solution of ( ) 1 chloro 1 phenylethane is toluene racemises slowly in the presence of a small amount of Sb 5, due to the formation of : (1) carbene () carbocation (3) free radical (4) carbanion Sol. () CH Sb 5 [ Ph CH CH ] [ Sb ] Planer structure The coagulating power of electrolytes having ions Na +, Al 3+ and Ba + for arsenic sulphide sol increases in the order: (1) (3) Na < Ba < Al () Al < Na < Ba (4) Ba < Na < Al Al < Ba < Na As S 3 is an anionic sol (negative sol) hence coagulation will depend upon coagulating power of cation, which is directly proportional to the valency of cation (Hardy-Schulze rule). 9. How many litres of water must be added to 1 litre of an aqueous solution of H with a ph of 1 to create an aqueous solution with ph of? (1).9 L (). L (3) 9. L (4).1 L Initial ph = 1, i.e. [H + ] =.1 mole/litre New ph =, i.e. [H + ] =.1 mole/litre In case of dilution: M 1 V 1 = M V.1 1 =.1 V V = 1 litre. Volume of water added = 9 litre. 1. Which one of the following molecules is expected to exhibit diamagnetic behaviour? (1) N () (3) S (4) C Sol. (1) & (4) both are correct answers. N Diamagnetic Paramagnetic S Paramagnetic FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

3 JEE (MAIN)-13-CMP -4 C Diamagnetic 11. Which of the following arrangements does not represent the correct order of the property stated against it? (1) Ni + < Co + < Fe + < Mn + : ionic size () Co 3+ < Fe 3+ < Cr 3+ < Sc 3+ : stability in aqueous solution (3) Sc < Ti < Cr < Mn : number of oxidation states (4) V + < Cr + < Mn + < Fe + : paramagnetic behaviour Sol. () & (4) both are correct answers) The exothermic hydration enthalpies of the given trivalent cations are: Sc +3 = 396 kj/mole Fe +3 = 449 kj/mole Co +3 = 4653 kj/mole Cr +3 = 4563 kj/mole Hence Sc +3 is least hydrated; so least stable (not most stable) Fe + contains 4 unpaired electrons where as Mn + contains 5 unpaired electrons hence (4) is incorrect. 1. Experimentally it was found that a metal oxide has formula M.98. Metal M, is present as M + and M 3+ in its oxide. Fraction of the metal which exists as M 3+ would be: (1) 4.8% () 6.5% (3) 5.8% (4) 7.1% Metal oxide = M.98 If x ions of M are in +3 state, then 3x + (.98 x) = x =.4 So the percentage of metal in +3 state would be %.98 = 13. A compound with molecular mass 18 is acylated with C to get a compound with molecular mass 39. The number of amino groups present per molecule of the former compound is: (1) 5 () 4 (3) 6 (4) R NH + CH C R NH C CH + H 3 3 Each CH3 C addition increases the molecular wt. by 4. Total increase in m.wt. = = 1 Then number of NH groups = = 14. Given E 3+ =.74 V; E + = 1.51 V Cr /Cr Mn 4 /Mn E = 1.33 V; E = 1.36 V 3+ Cr 7 /Cr / Based on the data given above, strongest oxidising agent will be: (1) Cr 3+ () Mn + (3) Mn 4 (4) As per data mentioned Mn is strongest oxidising agent as it has maximum SRP value. 4 FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

4 JEE (MAIN)-13-CMP Arrange the following compounds in order of decreasing acidity: H H H H (I) (II) N (III) (IV) (1) I > II > III > IV () III > I > II > IV (3) IV > III > I > II (4) II > IV > I > III Sol. () Correct order of acidic strength is III > I > II > IV 16. The rate of a reaction doubles when its temperature changes from 3K to 31K. Activation energy of such a reaction will be: (R = JK 1 mol 1 and log =.31) (1) 48.6 kj mol 1 () 58.5 kj mol 1 (3) 6.5 kj mol 1 (4) 53.6 kj mol 1 As per Arrhenius equation: k E æ a 1 1 ö ln = - k R ç - çè T T ø 1 1 E æ a 1 1 ö.33 log = - ç çè 31 3 ø E a = 53.6 kj/mole 17. Synthesis of each molecule of glucose in photosynthesis involves: (1) 1 molecules of ATP () 8 molecules of ATP (3) 6 molecules of ATP (4) 18 molecules of ATP Light reaction 1H + 1NADP + 18ADP ATP + 1NADPH 6C + 1NADPH + 18ATP C H + 1NADP + 18ADP + 6H Dark reaction Net reaction: 6C + 6H C6H Which of the following complex species is not expected to exhibit optical isomerism? (1) Co( en) (3) ( )( ) Co en NH Sol. () [Co(NH 3 ) 3 3 ] exists in two forms (facial and meridonial) () Co( NH ) (4) Co( en) FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

5 JEE (MAIN)-13-CMP -6 NH 3 NH 3 H 3 N H 3 N Co Co H 3 N NH 3 facial meridonial Both of these forms are achiral. Hence, [Co(NH 3 ) 3 3 ] does not show optical isomerism. 19. A piston filled with.4 mol of an ideal gas expands reversibly from 5. ml to 375 ml at a constant temperature of 37. C. As it does so, it absorbs 8J of heat. The values of q and w for the process will be: (R = J/mol K) (ln 7.5 =.1) (1) q = 8 J, w = 8 J () q = 8 J, w = + 8 J (3) q = + 8 J, w = + 8 J (4) q = + 8 J, w = 8 J Process is isothermal reversible expansion, hence U =. q = W As q = +8 J Hence W = 8 J. A gaseous hydrocarbon gives upon combustion.7 g of water and 3.8 g of C. The empirical formula of the hydrocarbon is: (1) C 3 H 4 () C 6 H 5 (3) C 7 H 8 (4) C H 4 æ yö y CxHy + ç x + ¾ ¾ xc + H çè 4ø Weight( g) 3.8 g.7 g moles.7.4 x.7 = y /.4 x 7 Þ = y 8 1. The order of stability of the following carbocations: CH H C CH CH ; H 3 C CH CH ; I II III is: (1) II > III > I () I > II > III (3) III > I > II (4) III > II > I rder of stability is III > I > II. FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

6 JEE (MAIN)-13-CMP-7 (Stability extent of delocalization). Which of the following represents the correct order of increasing first ionization enthalpy for Ca, Ba, S, Se and Ar? (1) S < Se < Ca < Ba < Ar () Ba < Ca < Se < S < Ar (3) Ca < Ba < S < Se < Ar (4) Ca < S < Ba < Se < Ar Sol. () Increasing order of first ionization enthalpy is Ba < Ca < Se < S < Ar 3. For gaseous state, if most probable speed is denoated by C*, average speed by C and mean square speed by C, then for a large number of molecules the ratios of these speeds are: (1) C*: C : C = 1.18 :1.5 :1 () C*: C : C = 1:1.18 :1.5 (3) C*: C : C = 1:1.15 :1.18 (4) C*: C : C = 1.5 :1.18 :1 Sol. () RT C* =, M 8RT C =, πm C = 3RT M 4. The gas leaked from a storage tank of the Union Carbide plant in Bhopal gas tragedy was: (1) Methylamine () Ammonia (3) Phosgene (4) Methylisocyanate It was methyl isocyanate ( NC) 5. Consider the following reaction: z xmn4 + yc4 + zh ¾ ¾ xmn + yc + H The values of x, y and z in the reaction are, respectively: (1), 5 and 8 (), 5 and 16 (3) 5, and 8 (4) 5, and 16 Sol. () Mn 5C 16H Mn 1C 8H x =, y = 5, z = Which of the following exists as covalent crystals in the solid state? (1) Silicon () Sulphur (3) Phosphorous (4) Iodine Silicon (Si) covalent solid Sulphur (S 8 ) molecular solid Phosphorous (P 4 ) Molecular solid Iodine (I ) Molecular solid 7. Compound (A), C 8 H 9 Br, gives a white precipitate when warmed with alcoholic AgN 3. xidation of (A) gives a acid (B), C 8 H 6 4. (B) easily forms anhydride on heating. Identify the compound (A). FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

7 JEE (MAIN)-13-CMP -8 (1) C H 5 () CH Br Br (3) CH Br (4) CH Br (A) CH Br AgN3( alc. ) [] CH CH (B) H + CH + AgBr ( pale yellow ) pthalic anhydride 8. Energy of an electron is given by æ - 18 Z ö ç E = J ç n. Wavelength of light required to excite an çè ø electron in an hydrogen atom from level n = 1 to n = will be (h = Js and c = ms 1 ) (1) m () m (3) m (4) m hc E = = Z 1 λ 7 λ = m 9. An organic compound A upon reacting with NH 3 gives B. n heating B gives C. C in presence of KH reacts with Br to give CH NH. A is (1) CH CH CH () H 3 C CH CH (3) CH CH (4) CH FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

8 JEE (MAIN)-13-CMP-9 CH C (A) NH3 H ¾ ¾¾ CH C (B) /(- H) NH 4 CH C (C) NH Br / KH CH NH 3. In which of the following pairs of molecules/ions, both the species are not likely to exist? (1) H, He () H, He (3) H, He (4) H, He Sol. () Bond order of H + and He is zero, thus their existence is not possible. FIITJEE Ltd., FIITJEE House, 9-A, Kalu Sarai, Sarvapriya Vihar, New Delhi -1116, Ph 4616, , Fax

Prerna Tower, Road No 2, Contractors Area, Bistupur, Jamshedpur , Tel (0657) , PART B CHEMISTRY

Prerna Tower, Road No 2, Contractors Area, Bistupur, Jamshedpur , Tel (0657) , PART B CHEMISTRY R Prerna Tower, Road No, ontractors Area, Bistupur, Jamshedpur 831001, Tel (0657)189, www.prernaclasses.com JEE MAIN 013 07 April 013 PART B HEMISTRY 31. Which of the following complex species is not expected