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    MAHESH JANMANCHI AIEEE 2006

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    Maximum Marks: 180

    Question paper format and Marking scheme:

    1. This question paper has 55 questions.

    2. Q No 1 to 10 carry 1.5 marks each ( 15 marks)

    3. Q No 11 to 35 carry 3 marks each ( 75 marks)

    4. Q No 36 to 55 carry 4.5 marks each ( 90 marks)

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    96. HBr reacts with CH2 = CH OCH3 under anhydrous conditions at room temperature to give

    (1) CH3CHO and CH3Br (2) BrCH2CHO and CH3OH

    (3) BrCH2 CH2 OCH3 (4) H3C CHBr OCH3

    Sol. (4)Electrophilic addition reaction is more favourable

    -HBr Br

    H C = CH - OCH H C - CH - OCH H C - CH - OCH2 3 2 3 3 3

    Br

    H

    97. The IUPAC name of the compound shown below is

    Cl

    Br (1) 2-bromo-6-chlorocyclohex-1-ene (2) 6-bromo-2-chlorocyclohexene

    (3) 3-bromo-1-chlorocyclohexene (4) 1-bromo-3-chlorocyclohexene

    Sol. (3)Priority is given to double bond. Numbering must be along the double bond

    98. The increasing order of the rate of HCN addition to compounds A D is

    (A) HCHO (B) CH3COCH3

    (C) PhCOCH3 (D) PhCOPh

    (1) A < B < C < D (2) D < B < C < A

    (3) D < C < B < A (4) C < D < B < A

    Sol. (3)Addition of HCN to carbonyl compounds is a nucleophilic addition reaction.

    Reactivity order :O

    ||

    H C H > R C H > R C R

    O

    ||

    O

    ||

    Ketones are less reactive than aldehydes due to +I effect of alkyl; group and steric hindrance.

    As the size of alkyl group increases , reactivity of ketones further decreases.

    Aromatic aldehydes and aromatic ketones are less reactive than their aliphatic analogues due to + R

    effect of benzene ring

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    99. How many moles of magnesium phosphate, Mg3(PO4)2 will contain 0.25 mole of oxygen atoms?

    (1) 0.02 (2) 3.125 102

    (3) 1.25 102

    (4) 2.5 102

    Sol. (2)

    1 mole of ( )Mg PO3 4 2 has 8 moles of O atoms? 0.25 moles of O atoms

    0.25

    8=

    2

    25

    8 100

    3.125 10

    =

    =

    100. According to Bohrs theory, the angular momentum of an electron in 5th

    orbit is

    (1)h

    25

    (2)h

    1.0

    (3)h

    10

    (4)h

    2.5

    Sol. (4)

    Angular momentum of e-in an orbit,

    nh

    mvr =

    5h2

    h2.5

    =

    =

    101. Which of the following molecules/ions does not contain unpaired electrons?

    (1) 22O

    (2) B2

    (3)2N+ (4) O2

    Sol. (1)

    22

    O : 2 * 2 2 * 2 2 2 2 * 2 * 21 1 , 2 2 , 2 , 2 2 , 2 2s s s s p p p p pz x y x y

    = = ( All paired e- - Diamagnetic)

    2B : 2 * 2 2 * 2 1 11 1 , 2 2 2 2s s s s p p

    x y = (2 unpaired e- - Paramagnetic)

    2N

    + : 2 * 2 2 * 2 2 2 11 1 , 2 2 2 2 2s s s s p p px y z

    = ( 1 unpaired e- - Paramagnetic)

    2O : 2 * 2 2 * 2 2 2 2 * 1 * 11 1 , 2 2 2 2 2 2 2s s s s p p p p p

    z x y x y = = (2 unpaired e- - Paramagnetic)

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    102. Total volume of atoms present in a face-centre cubic unit cell of a metal is (r is atomic radius)

    (1) 320

    3

    r (2) 324

    3

    r

    (3) 312

    3r (4) 3

    16

    3r

    Sol. (4)FCC unit cell contains 6Face centred and 8corner particles

    1 16 8

    2 8x x+ = 4

    So , FCC unit cell contains 4 particles

    Total volume of atoms present in a face-centre cubic unit cell of a metal

    =34

    4 3 r

    = 316

    3r

    103. A reaction was found to be second order with respect to the concentration of carbon monoxide. If

    the concentration of carbon monoxide is doubled, with everything else kept the same, the rate of

    reaction will

    (1) remain unchanged (2) triple

    (3) increase by a factor of 4 (4) double

    Sol. (3)

    [ ]2

    R CO - (1)

    [ ]' 22R CO - (2)

    '4

    R

    R=

    ' 4R R=

    104. Which of the following chemical reactions depicts the oxidizing behaviour of H2SO4?

    (1) 2HI + H SO I + SO + 2H O2 4 2 2 2

    (2) ( )Ca OH + H SO CaSO + 2H O2 2 4 4 2

    (3) NaCl + H SO NaHSO + HCl2 4 4

    (4) 52PCl + H SO 2POCl + 2HCl + SO Cl2 4 3 2 2

    Sol. (1)

    2HI + H SO I + SO + 2H O2 4 2 2 2

    In this reaction , oxidation no of iodine is increased from 1 to 0 and that of S is decreased from +6 to

    +4. Therefore H2SO4 is an oxidizing agent and HI is a reducing agent

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    105. The IUPAC name for the complex [Co(NO2)(NH3)5]Cl2 is

    (1) nitrito-N-pentaamminecobalt (III) chloride (2) nitrito-N-pentaamminecobalt (II) chloride

    (3) pentaammine nitrito-N-cobalt (II) chloride (4) pentaammine nitrito-N-cobalt (III) chloride

    Sol. (4)[Co(NO2)(NH3)5]Cl2pentaammine nitrito-N-cobalt (III) chloride

    106. The term anomers of glucose refers to

    (1) isomers of glucose that differ in configurations at carbons one and four (C-1 and C-4)

    (2) a mixture of (D)-glucose and (L)-glucose

    (3) enantiomers of glucose

    (4) isomers of glucose that differ in configuration at carbon one (C-1)

    Sol. (4)A pair of stereoisomers which differ in configuration at C -1 are called anomers and the carbon is called

    anomeric carbon

    - D (+) glucose and - D (+) glucose are anomers.

    107. In the transformation of 23892 U to

    234

    92 U , if one emission is an -particle, what should be the other

    emission(s)?

    (1) Two (2) Two and one +

    (3) One and one (4) One + and one

    Sol. (1)238 234 4 0U U + He + 2 e92 92 2 -1

    i.e., two

    108. Phenyl magnesium bromide reacts with methanol to give

    (1) a mixture of anisole and Mg(OH)Br (2) a mixture of benzene and Mg(OMe)Br

    (3) a mixture of toluene and Mg(OH)Br (4) a mixture of phenol and Mg(Me)Br

    Sol. (2)

    6 5 3 6 6 3( )C H MgBr CH OH C H Mg OCH Br + +

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    109. 3 3CH Br Nu CH Nu Br + +

    The decreasing order of the rate of the above reaction with nucleophiles (Nu) A to D is

    ( ) ( ) ( ) ( ) 3, , ,Nu A PhO B AcO C HO D CH O = (1) D > C > A > B (2) D > C > B > A

    (3) A > B > C > D (4) B > D > C > A

    Sol. (1)

    3CH O HO PhO AcO > > >

    If the nucleophilic atom is same , nucleophilicity parallels basicity. i.e., greater the basicity, stronger is

    the nucleophile.

    Weaker acid has the strong conjugate base

    110. The pyrimidine bases present in DNA are(1) cytosine and adenine (2) cytosine and guanine

    (3) cytosine and thymine (4) cytosine and uracil

    Sol. (3)DNA contains

    purines, Adenine and Guanine

    Pyrimidines Thymine and Cytosine

    111. Among the following the one that gives positive iodoform test upon reaction with I2 and NaOH is

    (1) CH3CH2CH(OH)CH2CH3 (2) C6H5CH2CH2OH

    (3) (4) PhCHOHCH3

    Sol. (4)

    Iodoform test is given by compounds having Methyl keto group ( CH3CO -) and Methyl carbinol(

    CH3CHOH -) groups

    12. The increasing order of stability of the following free radicals is

    (1) ( ) ( ) ( ) ( )

    CH CH< CH C C H C H C H C3 3 6 5 6 52 2 2 2< <

    (2) ( ) ( ) ( ) ( )

    C H C< C H CH< CH C < CH CH6 5 6 5 3 33 2 3 2

    (3) ( ) ( ) ( ) ( )

    C H C H< C H C < CH C < CH C H6 5 6 5 3 32 3 3 2

    (4) ( ) ( ) ( ) ( )

    CH CH< CH C < C H C < C H CH3 3 6 5 6 52 3 3 2

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    Sol. (1)

    The order of stability of free radicals is 30

    > 20

    > 10

    Benzyl free radicals are stabilized by resonance. So they are more stable than alkyl free radicals.

    As the no of phenyl groups attached to the carbon atom having odd e - increases, stability increases

    113. Uncertainty in the position of an electron (mass = 9.1 1031

    kg) moving with a velocity 300 ms1

    ,

    accurate upto 0.001%, will be

    (1) 219.2 10 m (2) 25.76 10 m

    (3) 21.92 10 m (4) 23.84 10 m

    ( )346.63 10 Jsh =

    Sol. (3)

    hx.V4m

    34

    31

    h 6.63 10x

    0.0014mV4 3.14 9.1 10 300

    100

    =

    34

    31 3

    6.63 10

    4 3.14 9.1 10 10

    =

    = 0.01933

    = 21.93 10

    114. Phosphorus pentachloride dissociates as follows, in a closed reaction vessel,( ) ( ) ( )

    5 3 2PCl g PCl g Cl g+

    If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of PCl5 is x,

    the partial pressure of PCl3 will be

    (1)1

    xP

    x

    + (2)

    2

    1

    xP

    x

    (3)1

    xP

    x

    (4)

    1

    xP

    x

    Sol. (1)

    ( ) ( ) ( )5 3 2

    PCl g PCl g Cl g+

    1 0 0(1-x) x x

    Total no of moles = 1+ xPartial pressure = Mole fraction x P total

    13

    xP P

    PCl x

    =

    +

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    115. The standard enthalpy of formation ( )0 Hf at 298 K for methane, CH4(g), is 74.8 kJ mol1

    . The

    additional information required to determine the average energy for C H bond formation wouldbe

    (1) the dissociation energy of H2 and enthalpy of sublimation of carbon

    (2) latent heat of vapourization of methane

    (3) the first four ionization energies of carbon and electron gain enthalpy of hydrogen

    (4) the dissociation energy of hydrogen molecule, H2

    Sol. (1)

    ( ) ( ) ( ) 122 ; 74.84C s H g CH g H kJmol + =

    In order to calculate the average energy of C H bond formation , the following data is needed

    ( ) ( ) ;C s C g H ( enthalpy of sublimation of carbon)

    ( ) ( )2 2 ;H g H g H ( enthalpy of bond dissociation of H2)

    116. Among the following mixtures, dipole-dipole as the major interaction, is present in

    (1) benzene and ethanol (2) acetonitrile and acetone

    (3) KCl and water (4) benzene and carbon tetrachloride

    Sol. (2)

    Dipole dipole interactions are present between the polar molecules, I which the positive pole of one

    molecule is attracted by the negative pole of another molecule.

    117. Fluorobenzene (C6H5F) can be synthesized in the laboratory

    (1) by heating phenol with HF and KF

    (2) from aniline by diazotisation followed by heating the diazonium salt with HBF4

    (3) by direct fluorination of benzene with F2 gas

    (4) by reacting bromobenzene with NaF solution

    Sol. (2)

    Ar NH + NaNO + 2 HCl Ar N N + NaCl + 2H O

    2 2 2

    Cl

    BALZ SCHIEMANN REACTION

    ++

    N2Cl

    HBF

    4

    -HCl

    N2BF

    4F

    + N2

    + BF3

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    118. A metal, M forms chlorides in its +2 and +4 oxidation states. Which of the following statements

    about these chlorides is correct?

    (1) MCl2 is more volatile than MCl4

    (2) MCl2 is more soluble in anhydrous ethanol than MCl4

    (3) MCl2 is more ionic than MCl4

    (4) MCl2 is more easily hydrolysed than MCl4

    Sol. (3)

    Acc to Fajan, Low charge on the ion favours formation of ionic bond and high charge on the ion

    favours covalent bond formation

    119. Which of the following statements is true?

    (1) H3PO3 is a stronger acid than H2SO3

    (2) In aqueous medium HF is a stronger acid than HCl

    (3) HClO4 is a weaker acid than HClO3

    (4) HNO3 is a stronger acid than HNO2

    Sol. (4)

    Higher the oxidation state of the central atom, greater is the acidic nature

    So, HNO3 is a stronger acid than HNO2

    HClO4 is a stronger acid than HClO3Greater the electronegativity and higher the oxidation state of central atom, greater is the acidic nature

    So, H2SO3is a stronger acid than H3PO3Due to higher bond dissociation energy and molecular association in HF , it is weaker than HCl

    120. The molar conductivities0

    NaOAc and0

    H Cl at infinite dilution in water at 25oC are 91.0 and

    426.2 S cm2/mol respectively. To calculate o

    0

    HOAc , the additional value required is

    (1)0

    H O2

    (2)0K Cl

    (3)0N aOH (4)

    0N aCl

    Sol. (4)

    ( )- +3 30 0 0CH COONa CH COO Na = + ............... 1

    ( )0 0 0HCl CH = + .................. 2Cl+

    ( )0 0 0NaCl Na = + .................. 3Cl

    3 3

    0 0 0 0

    CH CH COONa HCl NaCl = COOH +

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    121. Which one of the following sets of ions represents a collection of isoelectronic species?

    (1)+ - 2+ 3+K ,Cl ,Ca ,Sc (2) 2+ 2 + 2Ba ,Sr ,K ,S+

    (3) 3 2 2N ,O ,F ,S (4) 2 2Li ,Na ,Mg ,Ca+ + + +

    Sol. (1)

    + - 2+ 3+K ,Cl ,Ca ,Sc

    All of them have 18 e-

    122. The correct order of increasing acid strength of the compounds is

    (a) CH3CO2H (b) MeOCH2CO2H

    (c) CF3CO2H (d)

    (1) b < d < a < c (2) d < a < c < b(3) d < a < b < c (4) a < d < c < b

    Sol. (3)+I groups decrease the acidic nature( Me-)

    -I groups increase the acidic nature ( - F and OMe)

    123. In which of the following molecules/ions are all the bonds not equal?

    (1) SF4 (2) SiF4(3) XeF4 (4) 4BF

    Sol. (1)In SF4, Hybridisation of central atom S is sp

    3d. Its shape is distorted tetrahedral or see saw.

    Due to repulsion with equatorial bonds , axial bonds are elongated. So, the bond lengths of two axialbonds are greater than the three equatorial bonds

    124. What products are expected from the disproportionation reaction of hypochlorous acid?

    (1) HClO3 and Cl2O (2) HClO2 and HClO4

    (3) HCl and Cl2O (4) HCl and HClO3

    Sol. (4)

    33 ClO ClO 2 ClH H H +

    Oxidation state of Cl is increased from +1( HOCl) to +5(HClO3) and decreased to -1(HCl)

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    125. Nickel (Z = 28) combines with a uninegative monodentate ligand X to form a paramagnetic

    complex [NiX4 ]2

    . The number of unpaired electron(s) in the nickel and geometry of this complex

    ion are, Respectively

    (1) one, tetrahedral (2) two, tetrahedral

    (3) one, square planar (4) two, square planar

    Sol. (2)2 2 6 2 6 2 8

    28 Ni:1s 2s 2p 3s 3p 4s 3d

    2 2 2 6 2 6 8Ni :1s 2s 2p 3s 3p 3d+

    No of unpaired e-= 2

    126. In Fe(CO)5, the Fe C bond possesses

    (1) -character only (2) both and characters

    (3) ionic character (4) -character only

    Sol. (2)

    In metal carbonyls, metal Carbon bond possesses both and characters

    127. The increasing order of the first ionization enthalpies of the elements B, P, S and F (lowest first) is(1) F < S < P < B (2) P < S < B < F

    (3) B < P < S < F (4) B < S < P < F

    Sol. (4)

    IE increase from left to right in a period and decreases down the group .IE of P is greater than that of S, due to half filled configuration of P

    128. An ideal gas is allowed to expand both reversibly and irreversibly in an isolated system. If Ti is the

    initial temperature and Tf is the final temperature, which of the following statements is correct?

    (1) ( ) ( )T > Tf firrev rev

    (2) Tf> Ti for reversible process but Tf= Ti for irreversible process

    (3) ( ) ( )T Tf frev irrev= (4) Tf= Ti for both reversible and irreversible processes

    Sol. (1)

    >Wirrev rev

    W

    ( ) ( )T > Tf firrev rev

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    129. In Langmuirs model of adsorption of a gas on a solid surface

    (1) the rate of dissociation of adsorbed molecules from the surface does not depend on the surface

    covered

    (2) the adsorption at a single site on the surface may involve multiple molecules at the same time

    (3) the mass of gas striking a given area of surface is proportional to the pressure of the gas

    (4) the mass of gas striking a given area of surface is independent of the pressure of the gas

    Sol. (3)

    Langmuir Adsorption Isotherm gives information about the mass of gasn adsorbed per gram of

    adsorbent is related to the equilibrium pressure by the expressionaP

    x / m1 bp

    =

    +

    130. Rate of a reaction can be expressed by Arrhenius equation as:

    /E RTk Ae

    = In this equation, E represents

    (1) the energy above which all the colliding molecules will react

    (2) the energy below which colliding molecules will not react

    (3) the total energy of the reacting molecules at a temperature, T

    (4) the fraction of molecules with energy greater than the activation energy of the reaction

    Sol. (2)

    /E RTk Ae

    = Where E is activation energy i.e., min amount of energy required to be possessed by the reactant

    molecule for their collision lkead to the formation of products

    131. The structure of the major product formed in the following reaction is

    Cl

    I

    NaCN

    DMF

    (1) (2)

    CN

    CN

    Cl

    I (3) (4)

    Cl

    CN I

    CN

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    Sol. (4)

    Alkyl halides are more reactive than aryl halides. So, side chain is attacked

    Cl

    I

    NaCN

    DMF

    I

    CN

    132. Reaction of trans-2-phenyl-1-bromocyclopentane on reaction with alcoholic KOH produces

    (1) 4-phenylcyclopentene (2) 2-phenylcyclopentene

    (3) 1-phenylcyclopentene (4) 3-phenylcyclopentene

    Sol. (4)According to E2 mechanism.

    133. Increasing order of stability among the three main conformations (i.e. Eclipse, Anti, Gauche) of

    2-fluoroethanol is

    (1) Eclipse, Gauche, Anti (2) Gauche, Eclipse, Anti

    (3) Eclipse, Anti, Gauche (4) Anti, Gauche, Eclipse

    Sol. (3)

    2-Fluoroethanol

    Anti (or) staggered Eclipsed Skew or Gauche Fully eclipsed

    In gauche form , there is possibility of intra molecular hydrogen bonding

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    134. The structure of the compound that gives a tribromo derivative on treatment with bromine water

    is

    (1) (2)

    CH3

    OH

    CH OH2

    (3) (4)

    CH3

    OH

    CH3

    OH

    Sol. (1)Since the compound on treatment with Br2 H2O gives a tri bromo derivative , it must be m Cresol

    Because it has one o- and two p - positions free with respect to OH group

    135. The decreasing values of bond angles from NH3 (106o) to SbH3 (101

    o) down group-15 of the

    periodic table is due to

    (1) increasing bp-bp repulsion (2) increasing p-orbital character in sp3

    (3) decreasing lp-bp repulsion (4) decreasing electronegativity

    Sol. (4)

    In a group, from top to bottom , as the size of the atom increases , pure p orbitals are involved inbonding

    136.

    Me

    Me

    NEt

    n-BuOH The alkene formed as a major product in the above elimination reaction is

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    (1) (2) CH2 = CH2

    Me (3) (4)

    Me

    Me

    Sol. (4)

    Me

    Me

    NEt

    n-BuOH

    Me

    In Hofmann elimination, less sterically hinderd hydrogen is eliminated and hence less substitutedalkene is the major product

    137. The spin-only magnetic moment [in units of Bohr magneton,(B)] of Ni2+

    in aqueous solution

    would be (Atomic number of Ni = 28)

    (1) 2.84 (2) 4.90

    (3) 0 (4) 1.73

    Sol. (1)

    2 2 2 6 2 6 8 01 2 2 3 3 3 4Ni s s p s p d s+

    As H2O is a weak field ligand, no forcible pairing occurs

    Hence the complex formed will be sp3

    hybridized and tetrahedral in geometry.

    No of unp[aired e-s = 2

    Therefore, spin only magnetic moment ( 2)n n = +

    2(2 2) = + = 8 2.84 = = B.M

    138. The equilibrium constant for the reaction

    ( ) ( ) ( )3 2 21

    SO g SO g + O g2

    is 24.9 10cK= . The value of Kc for the reaction

    ( ) ( ) ( )2 2 32SO g +O g 2SO g will be

    (1) 416 (2) 2.40 103

    (3) 9.8 102

    (4) 4.9 102

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    Sol. (1)

    Equation is reversed and multiplied by 2;2

    1K =

    2K1

    2 2 2

    1

    (4.9 10 )K

    =

    410 100 100

    4.9 4.9 24.01

    = =

    = 416.49

    139. Following statements regarding the periodic trends of chemical reactivity ofthe alkali metals and

    the halogens are given. Which of these statements gives the correct picture?

    (1) The reactivity decreases in the alkali metals but increases in the halogens with increase in

    atomic number down the group(2) In both the alkali metals and the halogens the chemical reactivity decreases with increase in

    atomic number down the group

    (3) Chemical reactivity increases with increase in atomic number down the group in both the

    alkali metals and halogens

    (4) In alkali metals the reactivity increases but in the halogens it decreases with increase in atomic

    number down the group

    Sol. (4)

    140. Given the data at 250C,

    0Ag + I AgI + e ;E 0.152V = 0Ag Ag ;E 0.800Ve+ + =

    What is the value of splogK for AgI?

    RT2.303 =0.059 V

    F

    (1)-8.12 (2) +8.612

    (3) -37.83 (4) -16.13

    Sol. (4)

    ( ) ( )

    0

    AgI s +e Ag s +I ; E 0.152

    =

    0Ag Ag ;E 0.800Ve+ + =

    ( ) + 0AgI s Ag + I ; E 0.952 =

    0

    cell

    0.059E logK

    n=

    sp

    0.0590.952 logK

    1 =

    sp

    0.952logK 16.135

    0.059= =

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    141. The following mechanism has been proposed for the reaction of NO with Br2 to form NOBr:

    ( ) ( ) ( )2 2NO g Br g NOBr g+

    ( ) ( ) ( )2NOBr g NO g 2NOBr g+ If the second step is the rate determining step, the order of the reaction with respect to NO(g) is

    (1)1 (2) 0

    (3) 3 (4) 2

    Sol. (4)

    ( ) ( ) ( )2 2NO g Br g NOBr g+

    ( ) ( ) ( )2NOBr g g 2NOBr gNO+ ( Rate determining step)

    Therefore, [ ][ ]2R = K NOBr NO

    [ ] [ ][ ][ ][ ][ ]

    2 c 2

    c 2

    NOBr =K NO BrK.K NO Br NOR =

    [ ]2'=K NO Br

    2

    Therefore order of the reaction w r t NO is 2

    142. Lanthanoid contraction is caused due to

    (1) the appreciable shielding on outer electrons by 4f electrons from the nuclear charge

    (2) the appreciable shielding on outer electrons by 5d electrons from the nuclear charge

    (3) the same effective nuclear charge from Ce to Lu

    (4) the imperfect shielding on outer electrons by 4f electrons from the nuclear charge

    Sol. (4)

    Lanthanoid contration is due to ineffective shielding offered by f orbitals which inturn is due to their

    dispersed shape

    143. Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0.1 M is

    100 . The conductivity of this solution is 1.29 S m1

    . Resistance of the same cell when filled with

    0.2 M of the same solution is 520 . The molar conductivity of 0.2 M solution of the electrolyte

    will be

    (1) 4 2 1124 10 S m mol (2) 4 2 11240 10 S m mol

    (3)4 2 1

    1.24 10 S m mol

    (4)4 2 1

    12.4 10 S m mol

    Sol. (4)

    1K =

    R

    l

    a

    11.29 =

    100

    l

    a

    1129 ml

    a

    =

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    R = 520 , C = 0.2 M

    ( ) 1 11 1

    129 m

    520

    lK

    R a

    = =

    1000K

    im

    Molar ty =

    6 31 1000129 10520 0.2

    m=

    6129 1000 10520 0.2

    =

    31.24 10=

    = 4 2 112.4 10 S m mol

    144. The ionic mobility of alkali metal ions in aqueous solution is maximum for(1) K

    +(2) Rb

    +

    (3) Li+

    (4) Na+

    Sol. (2)Smaller the size, heavier is the hydration and lesser is the ionic mobility and vice versa.

    Rb+ is the largest ion among given. So it is least hydrated. Hence it will have maximum ionicmobility

    145. Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is

    (1) 11.14 mol kg (2) 13.28 mol kg

    (3) 12.28 mol kg (4) 10.44 mol kg

    Sol. (3)

    '

    1000 Mm

    1000 d MM

    =

    '

    1000 2.05m

    1000 1.02 2.05 x 60

    =

    = 2.28

    146. The enthalpy changes for the following processes are listed below:

    ( ) ( )2Cl g 2Cl g ,= 1242.3 kJmol

    ( ) ( )2l g 2l g ,= 1151.0 kJmol

    ( ) ( ) ( )ICl g l g Cl g ,= + 1211.3 kJmol

    ( ) ( )2 2I s l g ,= 162.76 kJmol

    Given that the standard states for iodine and chlorine are I2(s) and Cl2(g), the standard enthalpy

    of formation for ICl(g) is

    (1)-14.6 1kJmol (2) -16.8 1kJmol

    (3) +16.8 1kJmol (4) +244.8 1kJmol

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    Sol. (3)

    ( ) ( )2 21 1

    I Cl ICl g2 2s +

    ( ) ( )1 1 1

    2 2 22 2

    H H H H HI l Cl Cl I ClI s l g

    = + +

    ( )1 1 1

    62.76 151.0 242.3 211.32 2 2

    = + +

    = 228.03 211.3

    H =16.73

    147. How many EDTA (ethylenediaminetetraacetic acid) molecules are required to make an octahedral

    complex with a Ca2+ ion?(1)Six (2) Three

    (3) One (4) Two

    Sol. (3)

    EDTA is a hexa dentate ligand

    148.

    OH

    + CHCl +NaOH3

    O Na+

    CHO The electrophile involved in the above reaction is

    (1)dichloromethyl cation( )CHCl2 (2) dichlorocarbene( :CCl2)

    (3) trichloromethyl anion( )CCl3 (4) formyl cation ( )CHO

    Sol. (2)

    This is Reimer Tiemann reaction, in which the electrophile involved is dichloro carbene

    149. 18 g of glucose (C6H12O6) is added to 178.2 g of water. The vapour pressure of water for this

    aqueous solution at 100oC is

    (1) 759.00 Torr (2) 7.60 Torr

    (3) 76.00 Torr (4) 752.40 Torr

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    Sol. (4)0

    S

    S

    P P n

    P N

    =

    S

    S

    18 1760 P 0.1180 10

    178.2P 9.9 9.9

    18

    = = =

    S S

    1760 P P

    99 =

    S S760 99 P 99= P

    S760 99 100P =

    S

    760 99

    P 752.4100

    = =

    150. (H U) for the formation of carbon monoxide (CO) from its elements at 298 K is

    ( )1 1R = 8.314 J K mol

    (1)-1238.78 1J mol (2) 1238.78 1J mol

    (3) -2477.57 1J mol (4) 2477.57 1J mol

    Sol. (1)

    21C + O CO2

    gH U n RT =

    g

    1n = 1- 1

    2

    18.314 298

    2=

    1238.78=