Select the correct alternative. (Only one is correct) [27 × 3 = 81]
There is NEGATIVE marking. 1 mark will be deducted for eachwrong answer.
Q.25 Whichofthefollowingisincorrectstatement
(A) I3
– is linear in shape and consist 22 valence electrons
(B) HNCO and N3
– is linear in shape
(C)hydroxylamineis morenucleophilicthanNH3
(D*)AlN is more ionic than MgO
[Sol: (D)AlN is more ionic than MgO becuaseAl3+ has more polarising power than mg2+ but N3– and O2–
polarisationisnearlysame.]
Q.26 Forthefollowingreaction
CH3–CH2 – Cl + NaOH  CH3–CH2–OH+NaCl
If thereagent is NaOH the best solvent is
(A) water (B*) C2H5OH + H2O (C) C2H5OH (D) onlyNaOH
[Sol: (B) Alkyl halideis solubleinethanol& NaOHis solubleinwater ]
Q.27 Select thecorrect statement
(A) bond energy of N  N << P  P
(B) bond energy of P – P < N – N
(C*) Ti(H2O)3
+3 is a coloured compound in pure state
(D)AgI2
– is unstable whileAgF2
– is stable compound
[Sol: (C) Ti 22 ® 3d2, 4s2
Ti3+ = 3d1 1 unpairedso coloured ]
Q.28 Organiccompound(A)reactswithalc.KOHandgives (B),whichontreatmentwith NaOEt isomerizes
to (C). Compound (C), on treatment with OsO4 followed by HIO4 results CH3CH=O only. Select the
incorrect statement.IfAis amonohalogenhydrocarbon with molecularweight is 92.5.
(A) (A) gives yellow ppt. withAgNO3
(B) (A) do not give anyppt. withAgNO3 in NH3
(C) (C) gives brown ppt. withAgNO3/NH3
(D*) (A) reacts with NaI/acetone according to first order rate kinetics.
[Sol: (D) CH3–CH2–CH2–CH2–Cl ]
Q.29 If R–isomer have –ve rotation and S-isomer have +ve rotation, select the correct statement about the
mixture ofRandS 2–bromobutane,specificrotation ofmixture is +18.40 andspecificrotationofR–2–
bromobutane is –230 then select the incorrect statement
(A) S–isomer has 23% specific rotation
(B) 80% excess of S over R isomer
(C)R-isomerhas composition 10% only
(D*) None of these
[Sol: R - Isomer  –ve rotation
S-Isomer  +ve rotation
specific rotationof mix is =+18.4 (S excess)
specific rotation ofR-isomer(pure) = –23
specific rotation of S-isomer(pure) = +23
optical purity (ee) = 100
23
4
.
18
 = 80%
80% S (excess) + 20% (R + S) ]
XIII – SOLUTIONS CHEM PAPER -1 REVIEW TEST-3

Q.30 When2–chlorobutanereactswithNaOHinpresenceofethylalcoholand water,ratekineticsofreaction
follows
(A) (B)
(C) (D*)
[Sol: (D) rate = K1(R – X)1 (nu)1 + K2 (R – X)1 ]
Q.31 


H major product is
(A) (B) (C*) (D)
[Sol:
Q.32 Chirapos was developedbyprofessor Kagan &has founduseful applications in asymmetricsynthesis.
Usingfischerprojectionshownbelow,whichiscorrectstatement aboutconfigurationofthechiraposein
terms ofR/S notation.
(A) It is 2R, 3R molecule (B) It is 2S, 3R, molecule
(C*) It is 2S, 3S molecule (D) It is 2R, 3S molecule

Q.33 Inthefollowingreaction
Product is
(A) (B) (C*) (D)
[Sol:
Q.34 Select theincorrect statement
(A)Al3+ on treatment with aq. Na2S givesAl(OH)3
(B) Cr3+ on treatment with aq. Na2S gives Cr(OH)3
(C) Cr(OH)3 dissolvedin basic solution ofbrominewater
(D*)When mixtureofAgCl, Hg2Cl2 istreatedwithNH3 andresultant is filtered, blackresidue consist
HgNH2Cl,Hg, only
Q.35 For the reactions
I AcOH
NaOAc

 

II AcOH
NaOAc

 

Select thecorrect statement
(A*) rate of Ist reaction is 1011 times faster than trans IInd
(B) rate of IInd reaction is 1011 times faster than trans Ist
(C) rate of Ist reaction and IInd reaction are equal
(D)reactionnot possible

[Sol: anchimeric assistance throughbond. ]
Q.36 Theequilibriumconstant fortheionizationofR–NH2(aq)inwateras
R–NH2(g) + H2O(l)  R–NH2(aq) R–NH3
+(aq) + OH–(aq)
is 8 × 10–6 at 25°C. Find the pH of a solution at equilibrium with pressureof R–NH2(g) is 0.5 atm.
Assume Henry's Law, at equilibrium PA = K[A]; where K =1.[Take log 2.82 = 0.45]
(A) 12.3 (B*)  11.3 (C)  11.45 (D) None
[Sol. 8 × 10–6 =
5
.
0
x2
4 × 10–6 = x2
x = 2 × 10–3
 pOH = 2.7
So, pH = 11.3 ]
Q.37 Whichstatement(s)is/aretrueabout therelation betweenthefollowing compounds?
(a) (b) (c)
(I) a and b are tautomers (II) b and c are resonating structures
(III) a and c are resonating structures (IV) a and c are tautomers
(A*) I & III (B) II & IV (C) I, II & III (D) I & IV
Q.38 Arrangethefollowingcarbocationsintheincreasingorderoftheirstability.
(I) (II) (III)
(A*) I > II > III (B) I > II = III (C) I > III > II (D) III > I > II
[Sol. (I) Two benzenoid RS & Two H
(II) Two benzenoid RS & but zero H
(III) Onlyone benzenoid RS zero H ]
Q.39 Whichstatementaboutthefollowingequilibriumis/aretrue?
Ph3C–H +


K
O
Me 

K
C
Ph3 + MeOH
(I) The reactionfavours the product formation.
(II)Ph3CK is the dominant anionicspecies in this reaction.
(III) Methanol is the weaker acid in this reaction.
(IV) Thereactionfavours thereactant formation.
(A) I & II (B) I, II & III (C*) IV only (D) III & IV
[Sol. Reaction moves towards weaker acid & base ]

Q.40 Which one of following carbonyl compound when treated with dilute acid forms the most stable
carbocation?
(A) 3
3 CH
C
CH
||
O

 (B) (C*) (D) 5
6
5
6 H
C
C
H
C
||
O


[Sol. C will form aromaticcation byattack of Honcarbonyl oxygen.]
Q.41 Correct order ofheat of combustion is:
(p) 1,3-Pentadiene (q) 1,3-Butadiene
(r)2,3-Dimethyl-1,3-butadiene (s) Propadiene
(A) s > q > p > r (B) s > r > q > p (C*) r > p > q > s (D) s > r > p > q
[Sol. More theno. of C &H in the compound more will be heat of combustion]
Q.42 Writecorrect orderofreactivityoffollowinghalogenderivatives.
(I) (II) CH2=CH–Cl (III) Et3C–Cl (IV) PhCH2Cl (V) Ph3C–Cl
(A*) I > V > IV > III > II (B) V > IV > I > III > II
(C) V > I > IV > III> II (D) I > V > III > IV > II
[Sol. ReactivityofR–XincreaseswithdecreaseinBD.E.ofRX&increaseinstabilityofcarbocationformed.]
Q.43 Correctorderofnucleophilicityoffollowinganionsinpolarproticsolventis:
(A*)

3
CH >
-
2
NH >

OH >

F (B)

3
CH <
-
2
NH <

OH <

F
(C)

3
CH =
-
2
NH =

OH =

F (D)

3
CH >

F >

OH >
-
2
NH
[Sol. Nucleophilicitydecreaseswithincreasein electronegativityofdonoratom.]
Q.44 NO2 isinvolvedintheformationof smogand acidrain.Areaction that is important in theformation of
NO2 is
O3(g) + NO(g) O2(g) + NO2(g) K = 6 × 1034
If the air over a section of Pooja Towers contained 1.0 × 10–6M O3, 1.0 × 10–5M NO, 2.5 × 10–4M
NO2 and 8.2 × 10–3M O2, what can we conclude
(A) there will be a tendencyto form more NO and O3
(B*) there will be a tendencyto form more NO2 and O2
(C) There will be a tendencyto form more NO2 and O3
(D)Therewill be no tendencyforchangebecause thereaction is at equilibrium
[Sol: Q =
  
  
NO
O
NO
O
3
2
2
= 5
6
4
3
10
0
.
1
10
0
.
1
10
5
.
2
10
2
.
8










= 2.05 × 105
As Q < K
Thus forwardreaction will take place ]

Q.45 The equilibrium SO2Cl2(g) SO2(g)+ Cl2(g) is attained at 250C in aclosed container and Helium
is introduced.Whichofthefollowingstatementis correct
(1) The concentrations of SO2, Cl2 and SO2Cl2 change
(2)Morechlorine is formed
(3) Concentration of SO2 is reduced
(4) More SO2Cl2 is formed
(A) 1, 2, 3 (B) 2, 3, 4 (C) 3, 4 (D*) noneof these
[Sol: AtconstantvolumeadditionofinertgasHeliumdoesnoteffect theequilibrium]
Q.46 In the system LaCl3(s) + H2O(g) + heat LaClO(s) + 2HCl (g) equilibrium is established. More
water vapour is added to re-establish the equilibrium. The pressure of water vapour is doubled. The
factor bywhich pressure of HCl is changed is
(A) 2 (B*) 2 (C) 3 (D) none of these
[Sol: LaCl3(s) + H2O(g) + heat LaClO(s) + 2HCl (g)
K =
 
 
O
H
HCl
2
2
After doubling the concentration of H2O [H2O]new = x
[H2O] = x Andat equation, [HCl]new = 2 · [HCl]
Q.47 Whichofthefollowingcompoundhaspyramidalgeometry?
(A) B(CH3)3 (B) (CH3)3C (C*) (CH3)3N (D) BF3
Q.48 20 ml of0.2 M – NaOHand 40 ml 0.1 M – H2SO4 are mixed together in a flask & volume made up to
250 ml.The pHof theresultant solution is
(A) 5 (B) 6 (C) 8 (D*) noneof these