objective questions on chemistry for IITJEE

PART A

1. N O + CH2COCl CH2COClEt3N

H2OC10H12O3(P)

A. O

O

O

B.

O

OO

C.

OH

OO

D.

OH

OO

2.O

D

OOH−

XCH2 CH COCH3

H2OY

dil. NaOHD2O

Z

The compound Z will be:

A.

O

O

B.

OO

C.

O

D

O

D.

O−

O

3.

Ph C

O

C

O

Ph + Ph CH2 C

O

CH2 Ph NaOHC2H5OH

What is the product of the above reaction?

A.

Ph

O

PhB.

Ph

O

Ph

Ph

Ph

C.

Ph

O

Ph

Ph

Ph

D.

Ph

O

Ph

4.

O

OC2H5MgBr

H3O+ B

What is the compound B?

A. H5C2

OH

C2H5

OH

B.

OH

C2H5

O

C. H5C2 CH

OH

CH2CH2CH2OH

D.

C2H5

C2H5

O

5.

O

D

O

OH−A

A

O

H2OB

Bdil.NaOH

∆X

What is the product X of the above reaction?

A.

O

O−

O

B.

O−

O

O

C.

O

D

O

D.

O

O

D

6. DEtBr

CLDA

−780C

CH3

O

NaOEt/EtOH

room temp.A

EtBrB

Then products B and D are respectively:

A.

CH3

O

C2H5

and

CH3

C2H5

O

B.

CH3

C2H5

O

and

CH3

O

C2H5

C. Both

CH3

C2H5

O

D. Both

CH3

O

C2H5

7. Pick the choice that tells the product and the title of the reaction:

O

+ OC2H5

O

H5C2O

NaH

A.

COOC2H5

O

(Crossed Claisen Condensation)

B.

OC2H5

OC2H5

(Retro-Aldol Condensation)

C.

OC2H5

OC2H5

(Claisen-Schmidt Condensation)

D.

OH

and H5C2

O

OH

(Cannizaro reaction)

8. A. dihalogen derivative(A) of a hydrocarbon having two C-atoms reacts with alc.KOHand forms another hydrocarbon which gives a red ppt. with ammoniacal Cu2Cl2. Com-pound A. gives an aldehyde when treated with aq. KOH. The IUPAC Name of A. isx,y−dichloroethane, x+y is

A. 2

B. 3

C. 4

D. 6

9. For the reaction A(g) B(g)at equilibrium, the partial pressure of B. is found tobe one fourth of the partial pressure of A. S of the ∆Go for the reaction A(g) B(g)isRTlnX. Then the value of X will be

A. 2

B. 3

C. 4

D. 6

10. The half life period and the initial concentration for a reaction are as follows. The orderof the reaction isinitial concentration : 350 540 158t1/2 : 425 275 941

A. 2

B. 3

C. 4

D. 6

11. Gold has a close-packed structure which can be viewed as spheres occupying 0.74 of thetotal volume. What is the radius of the gold ion if the density of gold is 19.3g/cc?(Au=197amu)

A. 1.439× 10−8 cm

B. 4.07× 10−8 cm

C. 1.017× 10−8 cm

D. 8.23× 10−8 cm

12. Pure benzene freezes at 5.3oC. A. solution of 0.223 g of phenylacetic acid C.6H5CH2COOHin 4.4 g of bezene (Kf=5.12 K kg mol−1) freezes at 4.47oC. From this observation, onecan conclude that

A. Phenyl acetic exists as such in benzene

B. Phenyl acetic acid undergoes partial ionisation in benzene

C. Phenyl acetic acid undergoes complete ionisation in benzene

D. Phenyl acetic acid dimerizes in benzene

13. CF3CO3H

H2OA.

Conc. H2SO4

∆B.

A. and B. are respectively

A.

OHOH

and

B.

OH

OH

and

C.

OH

OH

and

O

D.

OHOH

and

O

14. Ph

H

CH3

H

OH

CH3

Lucas reagentm(all compunds possible)

Fractionaldistillation

n

Then the value of n is

A. 2

B. 3

C. 4

D. 5

Paragraph for Question Nos. 15 to 17

KMnO4,cold

NaIO4[Q]C11H12O2

NaOH

H+,∆[R]C11H12O2

[R]CH3MgBr(excess)

HBr[S]C13H9BrO NaH

O

Answer the questions based on the above passsage

15. The compound [S] is

A.C2H5

OH

B.

OH

CH2Br

CH2OH

C.

OH

CH3

CH3

Br

CH2OH

D.

OH

OH

Br

CH2Br

16. In the transformation of [Q] into [R], which of the following statements are correct.

A. Hydride formation is rate determining

B. Attack of OH− is rate determining

C. Reaction is independent of the OH− concentration

D. Reaction is independent of the reactant concentration

17. Compound [R] is

A.

O

O

B.

O

O

C.

CH3

OH

CH3

OH

D. O

O

18. Pure Na2C2O4 and KHC2O4.H2C2O4 are mixed in such a proportion that each gram ofthe mixture reacts separately with equal volumes of 0.1 M KMnO4 and 0.1 M NaOH.Suppose x is the ratio of the mass of Na2C2O4 and KHC2O4.H2C2O4. Then find [x]where [.] represents the gif.

A. 2

B. 4

C. 5

D. 3

19. In Kjeldahl’s method of estimation of nitrogen, K2SO4 acts as

A. an oxidising agent

B. boiling point elevator

C. boilling point depressor

D. catalytic agent

20. Number of π-bonds in Fe2(CO)9 is X and Xn =3, then value of n will be

A. 4

B. 5

C. 2

D. 3

21. In homologues series of ethers starting from the first to seventh member how manymember(s) can exhibit metamerism as well as optical isomerism?

A. 4

B. 5

C. 2

D. 3

22. Which of the following statements is correct about the colloids?

A. Lyophillic sols have almost similar stability than lyophobic sols

B. Greater extent of Tyndall effect is observed in lyophillic sols

C. Lyophillic sols have large particle size than that of lyophobic sols in general

D. The charge on the lyophobic sols is independent of the pH

23.

O

O

(P)

O

O

(Q)

OO

(R)

O

O

(S)

O

O

(T)

Which of the following statements is true for the compounds above?(More than oneoption may be correct)

A. Compound (P) has a higher reduction potential than (Q)

B. Compound (T) has a higher reduction potential than (S)

C. Compound (R) has highest reduction potential among (P), (Q) and (R)

D. Compound (P) has higher tendency to undergoe enolization than compound (Q)

24. 0.98 g chloroplatinate salt of a monoacidic base when ignited, left 0.39 g of platinumresidue. The relative molecular mass of the base is

A. 40

B. 80

C. 160

D. 240

25. Which of the following fails the azo-dye test?

A.

NH2

NH2

B.

H2N

NH2

C.

NH2

NH2

D.

NH2

26. For a fairly concentrated solution of a weak electrolyte AxBy, the degree of dissociationis given by

A. α =√Keqxy/C.

B. α =√Keq.C./xy

C. α =√Keq/C.(x+ y)

D. α = Keq/Cx+y−1xxyy

1/x+y

27. A. certain compound was known to have a formulae which could be represented as[PdCxHyNz](ClO4)2 Analysis shed that the compound contained 30.15% carbon and5.06% hydrogen. When converted to the corresponding thiocyanate [PdCxHyNz](SCN2)2,the analysis was 40.46% carbon and 5.94% hydrogen. Calculate the values x,y and zrespectively.

A. 12, 28, 4

B. 14, 26, 2

C. 14, 28, 4

D. 12, 26, 3

28. In an oil drop experiment, the terminal velocity of an oil droplet was observed to be1.00 mm/s. The density of the oil is 0.850 g/cm3, and the viscosity of air is 1.83×10−5.Calculate the mass of the air droplet.

A. 1.10×10−6 g

B. 1.10×10−6 kg

C. 1.10×10−15 kg

D. 1.10×10−13 kg

29. Examples of isoters are

A. CO2 and SO2

B. CO2 and N2O

C. NO2 and SO2

D. all of these

30. Novolac is

A. linear condensation product of phenol and formaldehyde

B. cross linked condensation product of urea and formaldehyde

C. cross linked condensation product of phenol and formaldehyde

D. linear condensation product of urea and formaldehyde

31. The number of S-O-S bonds in γ-SO3 is

A. 0

B. 2

C. 3

D. 1

32. 7.5 mL of gaseous hydrocarbon was exploded with 36 mL of oxygen. The volume ofgases on cooling was found to be 28.5 mL,15 mL of which was absorbed by KOH andthe rest was absorbed by a solution of alkaline pyragallol. If all volumes are measuredunder the same conditions, no. of H atoms in the hydrocarbons is

A. 5

B. 4

C. 6

D. 7

33. In a gravimetric determination of phosphorus, 0.248 g of an organic compound wasstrongly heated in a Carius tube with concentrated nitric acid. Phosphoric acid soproduced was precipitated as MgNH4PO4 which on ignition yielded 0.444 g of Mg2P2O7.The percentage of phosphorus in the compound is given by x×10. Value of x is

A. 5

B. 4

C. 6

D. 7

34. After electrolysis of a sodium chloride (NaCl) solution with inert electrodes for a certainperiod of time, 600 mL of the solution was left which was found to be 1 N in sodiumhydroxide, During the same time 31.8 g of Cu was deposited in a Cu voltameter in serieswith the electrolytic cells. The percentage of theoretical yield of the sodium hydroxideobtained is x×10. Value of x is given by

A. 5

B. 4

C. 6

D. 7

35. Enthalpy is equal to

A. T2[∂(G/T)/∂T]P

B. -T2[∂(G/T)/∂T]P

C. T2[∂(G/T)/∂T]V

D. -T2[∂(G/T)/∂T]V

36. The emf of the cell, H2(g)|Buffer||Normal Calomel Electrode is 0.720 volt at 40oC. whenthe barometric pressure is 760 mm. The pH of the buffer solution is(Ecalomel=0.28 volt)

A. 5

B. 4

C. 6

D. 7

37. The density of an equilibrium mixture of N2O4 and NO2 at 1 atm and 348 K is 1.84 g/L.Kc for the equilibrium is

A. 12

B. 9

C. 6

D. 8

38. Bromine is added to cold dilute aqueous solution of NaOH and the mixture is boiled.The greatest difference between the various oxidation states of bromine is

A. 5

B. 4

C. 6

D. 7

39. Which of the following reactions will not succeed?

A. CH3 CH2 Cl + NaIacetone

B. CH3 CH2 Br + LiIacetone

C. CH3 CH2 I + LiClacetone

D. CH3 CH2 I + NaClacetone

40. HNHN2HClH2O

The product of the above reaction sequence is

A.

NN

B.

NH2H2N

C.

H2N

(2 moles)

D.

41. The monomer of polymer orlon is

A. vinylidene chloride

B. methylmethacrylate

C. acrylonitrile

D. propylene

42.

COOH

I2NaHCO3

A.

Then the major product A. is

A.

O

OI

B.

O

OI

C.I

I COOH

D.I

COOH

43. Given is the pKa for the following organic compounds

CH3

pK1

pK2

Ph

Ph

H

pK3

Given the quantitites α=pK1/pK2, β=pK1/pK3, and γ=pK3/pK2 then which of thestatement given below is true?

A. α > β and α > γ

B. α > β and γ > α

C. β > γ and α > γ

D. β > γ and γ > α

44. Given is the compound

OCH3

N(Me)2N(Me)2

OH3C

Assertion (A) : The above compound is practically monoacidic.Reason (R) : One of the nitrogen is out of plane with respect to the other nitrogen.Which of the above statements is correct?

A. A is correct and R is the correct explanation of A.

B. A and R both are correct but R is not the correct explanation of A.

C. A is correct but R is false.

D. A is false but R is true.

45. Among the 3d transition metals Sc, Ti, V and Cr which has the most negative latticeenthalpy?

A. Sc

B. Ti

C. V

D. Cr

46. Sanger’s reagent is used for the identification of :

A. N-terminal of a peptide chain

B. C-terminal of a peptide chain

C. side chain of a amino acid

D. molecular weight of the peptide chain

47. If the Aufbau rule is not followed in filling of orbitals then the block of the element willchange in

A. K(19)

B. Sc(21)

C. V(23)

D. Ni(28)

48. What is the Kb of a weak base that produces one OH− per molecule if a 0.050 M solutionis 2.5% ionized?

A. 7.8 × 10−8

B. 1.6 × 10−6

C. 3.2 × 10−5

D. 1.2 × 10−3

49. Which of the following statements given below is true ?(More than one option maybe correct)

A. Equilibrium of a reaction is always affected by temperature.

B. The order of pre exponential factor is of the order 105.

C. Units of A for a zero order reaction is mol.L−1.s−1.

D. If a reaction is an elementary bimolecular process then it obeys second orderkinetics while the converse is not true.

50. The disulfide bonds which stabilize the structure of many proteins are due to

A. Due to oxdiation of two sulfate moieties

B. Oxidation of thiol moiety of cysteine

C. Condensation of two methionene residues

D. Condensation of two serine residues

objective questions on chemistry for IITJEE

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