Saturday, October 10, 2009

IIT-JEE-Chemistry-Final Revision Set No.90

1. Consider a titration of potassium dichromate solution with acidified Mohr's salt solution using diphenylamine as indicator. The number of moles of Mohr's salt required per mole of dichromate is

(A) 3

(B) 4

(C) 5

(D) 6

2.The correct statement(s) regarding defects in solids is(are)

(A) Frenkel defect is usually favoured by a very small difference in the sizes of cation and anion

(B) Frenkel defect is a dislocation defect

(C) Trapping of an electron in the lattice leads to the formation of F-center

(D) Schottky defects have no effect on the physical properties of solids


Paragraph

p-Amino-N, N-dimethylaniline is added to a strongly acidic solution of X. The resulting solution is treated with a few drops of aqueous solution of Y to yield blue colouration due to the formation of methylene blue. Treatment of the aqueous solution of Y with the reagent potassium hexcyanoferrate (II) leads to the formation of an intense blue precipitate. The precipitate dissolves on excess addition of the reagent. Similarly, treatment of the solution of Y with the solution of potassium hexacyanoferrate (III) leads to a brown colouration due to the formation of Z.

3. The compound X is

(A) NaNO3

(B) NaCl

(C) Na2SO4

(D) Na2S

4. The compound Y is

(A) MgCI2

(B) FeCI2

(C) FeCI3

(D) ZnCI2

5. The compound Z is

(A) Mg2[Fe(CN)6]

(B) Fe[Fe(CN)6]

(C) Fe4[Fe(CN)6]3

(D) K2Zn3[Fe(CN)6]2


Source JEE 2009 Paper 1

IIT-JEE-Chemistry-Final Revision Set No.89

1. STATEMENT-1 : There is a natural asymmetry between converting work to heat and converting heat to work.

and

STATEMENT-2 : No process is possible in which the sole result is the absorption of heat from a reservoir and its complete conversion into work.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True


Paragraph BASED QUESTIONS

In hexagonal systems of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism. Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them. A space-filling model of this structure, called hexagonal close-packed (HCP), is constituted of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible. Three spheres are then placed over the first layer so that they touch each other and represent the second layer. Each one of these three spheres touches three spheres of the bottom layer. Finally, the second layer is covered with a third layer that is identical to the bottom layer in relative position. Assume radius of every sphere to be 'r'.

2. The number of atoms in this HCP unit cell is

(A) 4

(B) 6

(C) 12

(D) 17

3. The volume of this HCP unit cell is

(A) 24 √2 r³

(B) 16 √2 r³

(C) 12 √2 r³

(D) 64/3√3 r³

4. The empty space in this HCP unit cell is

(A) 74%

(B) 47.6%

(C) 32%

(D) 26%

5. Identify the process used to extract the metal/compound from the given ore

Roasting, Calcinations, Carbon reduction, Self reduction


PbS --> PbO

CaCO3 --> CaO

ZnS --> Zn

Cu2S --> Cu


Source: IIT JEE 2008 paper 2

IIT-JEE-Chemistry-Final Revision Set No.88

1. The IUPAC name of [Ni(NH3)4] [NiCI4] is

(A) Tetrachloronickel (II) - tetraamminenickel (II)

(B) Tetraamminenickel (II) - tetrachloronickel (II)

(C) Tetraamminenickel (II) - tetrachloronickelate (II)

(D) Tetrachloronickel (II) - tetraaminenickelate (0)

2. STATEMENT-1 : Aniline on reaction with NaNO2/HCI at 0°C followed by coupling with β-naphthol gives a dark blue coloured precipitate.

and

STATEMENT-2 : The colour of the compound formed in the reaction of aniline with NaNO2/HCI at 0°C followed by coupling with b-naphthol is due to the extended conjugation.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

3. STATEMENT-1 : [Fe(H2O)5NO]SO4 is paramagnetic.

and

STATEMENT-2 : The Fe in [Fe(H2O)5NO]SO4 has three unpaired electrons.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

4. STATEMENT-1 : The geometrical isomers of the complex [M(NH3)4CI2] are optically inactive.

and

STATEMENT-2 : both geometrical isomers of the complex [M(NH3)4CI2] possess axis of symmetry.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

5. Electrolysis of dilute aqueous NaCI solution was carried out by passing 10 milli ampere current. The time required to liberate 0.01 mol of H2 gas at the cathode is (1 Faraday = 96500 C mol-1)

(A) 9.65 × 104 sec

(B) 19.3 × 104 sec

(C) 28.95 × 104 sec

(D) 38.6 × 104 sec


Soucre iit jee paper 2 2008

IIT-JEE-Chemistry-Final Revision Set No.87

1. STATEMENT-1 : Alkali metals dissolve in liquid ammonia to give blue solutions.

because

STATEMENT-2: Alkali metals in liquid ammonia give solvates species of the type [M(NH3)n]+ (M = alkali metals).

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

2. STATEMENT-1: Molecules that are not superimposable on their mirror images are chiral.

Because

STATEMENT-2: All chiral molecules have chiral centers.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True


3. STATEMENT-1: Band gap is germanium is small.

Because

STATEMENT-2: The energy spread of each germanium atomic energy level is infinitesimally small.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

source: 2007 JEE paper 2

4. Among the following, the coloured compound is

(A) CuCI

(B) K3 [Cu(CN)4]

(C) CuF2

(D) [Cu(CH3CN)4]BF4

5. Both [Ni(CO)4] and [Ni(CN)4]2- are diamagnetic. The hybridization of nickel in these complexes, respectively, are

(A) sp3, sp3

(B) sp3, dsp2

(C) dsp2, sp3

(D) dsp2, dsp3


source: 2008 JEE, Paper 2

IIT-JEE-Chemistry-Final Revision Set No.86

1. The number of stereoisomers obtained by bromination of trans-2-butene is

(A) 1

(B) 2

(C) 3

(D) 4


2. A positron is emitted from 23Na11. The ratio of the atomic mass and atomic number of the resulting nuclide is

(A) 22/10

(B) 22/11

(C) 23/10

(D) 23/12

3. For the process H2O(l), (1 bar, 373 K) → H2O(g) (1 bar, 373 K), the correct set of thermodynamic parameters is

(A) DG = 0, DS = +ve

(B) DG = 0, DS = -ve

(C) DG = +ve, DS = 0

(D) DG = -ve, DS = +ve

4. Consider a reaction aG + bH → Products. When concentration of both of the reactants G and H is doubled, the rate increases by eight times. However, when concentration of G is doubled keeping the concentration of H fixed, the rate is doubled. The overall order of the reaction is

(A) 0

(B) 1

(C) 2

(D) 3

STATEMENT-1: Glucose gives a reddish-brown precipitate with Fehling's solution.

Because

STATEMENT-2: Reaction of glucose with Fehling's solution gives CuO and gluconic acid.

(A) Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True




Source: 2007 JEE paper 2

IIT-JEE-Chemistry-Final Revision Set No.85

A 4.0 molar aqueous solution of NaCI is prepared and 500 mL of this solution is electrolysed. This leads to the evolution of chlorine gas at one of the electrodes (atomic mass: Na = 23, Hg = 200; 1 Faraday = 96500 coulombs).

1. The total number of moles of chlorine gas evolved is

(A) 0.5

(B) 1.0

(C) 2.0

(D) 3.0

2. If the cathode is a Hg electrode, the maximum weight (g) of amalgam formed from this solution is

(A) 200

(B) 225

(C) 400

(D) 446

3. The total charge (coulombs required for complete electrolysis is

(A) 24125

(B) 48250

(C) 96500

(D) 19300
--------------------

4. Consider a titration of potassium dichromate solution with acidified Mohr's salt solution using diphenylamine as indicator. The number of moles of Mohr's salt required per mole of dichromate is

(A) 3

(B) 4

(C) 5

(D) 6

5. Among the following metal carbonyls, the C-O bond order is lowest in

(A) [Mn(CO)6]+

(B) [Fe(CO)5]

(C) [Cr(CO)6]

(D) [V(CO)6]-

Source: 2007 JEE paper 2

IIT-JEE-Chemistry-Final Revision Set No.84

1. The structure of XeO3 is

(A) linear

(B) planar

(C) pyramidal

(D) T-shaped

2. XeF4 and XeF6 are expected to be

(A) oxidizing

(B) reducing

(C) unreactive

(D) strongly basic

3. STATEMENT-1

Micelles are formed by surfactant molecules above the critical miceller concentration (CMC).

Because

STATEMENT-2

The conductivity of a solution having surfactant molecules decreases sharply at the CMC.

(A) Statement-1 is True, Staement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Staement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

4. p-Hydroxybenzoic acid has a lower boiling point than o-hydroxybenzoic acid.

Because

STATEMENT-2

o-Hydroxybenzoic acid has intramolecular hydrogen bonding.

(A) Statement-1 is True, Staement-2 is True, Statement-2 is a correct explanation for statement-1.

(B) Statement-1 is True, Staement-2 is True, Statement-2 is not a correct explanation for statement-1.

(C) Statement-1 is True, Statement-2 is False

(D) Statement-1 is False, Statement-2 is True

5.

Match the chemical substances in Column I with type of polymers/type of bonds in Column II.



Column I -------Column II


Cellulose -- Synthetic polymer




Nylon-6, 6 -- Glycoside linkage



Protein-----Amide linkage



Sucrose---- Natural polymers


Source: 2007 JEE paper 1