Docstoc

Class XII Chemistry 2012 Question Paper (Set 2)

Document Sample
Class XII Chemistry 2012 Question Paper (Set 2) Powered By Docstoc
					I Series : SMAlII                                                                                             m;:f.
                                                                                                                                 56/1/2
                                                                                                              Code No.
-mt;:f.                                                                                            ~.                 ~
                                                                                                                   CfiT-~             *" lf9-%
Roll No.                                                                                           1R~m-1
                                                                                                    Candidates must write the Code on
                                                                                                    the title page of the answer-book.


  •       ~                  ~-'q;pi ~ % 11 ~ I
                     \itTq Cf){ B fcp~
  •       ~-'Q;f.qOO~ctram-~w.~CfiT~~-~*"lf9-%1Rm-                                                                                I
  •       ~            \
                     itTq Cf){B fcp~              ~-~            l{   0~          ~ I
  •    ~~CfIT~fH&'1I~m~~,~CfIT~~n                                                                                  I
                                                                                        m Tr:ITt
  •       ~ ~-~
       fct;<:rr~
       ~1RCfiTt~~~
                                CfiT
                                I
                                   ~
                                    10.15 ~
                                            *"~     15 RenT
                                                  ~ 10 Cf\if {fCfi~
                                                      .3
                                                             I
                                                               wr:f
                                                                                         ~   ~-~
                                                                                                   I ~-'Q;f enT~
                                                                                                       i$T ~~          ~
                                                                                                                           ~.q
                                                                                                                              *"~ ct~-10.15 ~



  •       Please check that this questio paper contains 11 printed pages.
  •       Code number given on the rig hand side of the question paper should be written on the
          title page of the answer-book y the candidate.
  •       Please check that this questio paper contains 30 questions.
  •       Please write down the Seri      u~er of the question before attempting it.
  •       15 minutes time has been all ed to read this question paper. The question paper will be
          distributed at 10.15 a.m. F    10.15 a.m. to 10.30 a.m., the students will only read the
          question paper and will not  ite any answer on the answer script during this period.

                                                        ~~I~w{fcmT;:r~

                                                        CHEMISTRY (Theory)
FMftrr WflT           : 3   cru?:j                                                                                          [~3fcn;             70
Time allowed : 3 hours                  J                                                                              [ Maximum marks: 70

fllqlR4~:

              (i)           ~rrFr~t                      I
              (ii):         ~        rrFf c/;" tJ7"IF{ frti ~
                                                     3                     T([[   tI
              (iii)         rrFf-?i&rr 1    "# 8 W6".3ffrr ffFl-~        rrFf t I ~      rrFf c/;" fcr!rr 1 3fcn t I

              (iv)          rrFf-?i&rr 9 "# 18 (fEfi" ffFl-~         rrFf t I ~      rrFf c/;" fcr!rr 2 3fcn t I

              (v)           rrFf-?i&rr 19 "# 2 rtcfi" 'Jft ffFl-~         rrFf t I ~       rrFf c/;" fcr!rr 3 3fcn t I

              (vi)          rrFf-?i&rr 28 "# 3 fW-~              rrFf t I ~       rrFf c/;" fcr!rr 5 3fcn t I
              (vii)         3fICf:t4ChrtljRJ< M'frT ~      q;r Jflllrr q;f I 4i('tjikd c/;" ~          qff arpTfrr ;rtJ.t I

56/112                                                                        1                                                          [P.T.O.

                                                                                                                                                     1
                                                                                                                                                     f-.
          General Instructions :
                        (i)         All questions are compulsory.
                        (ii)        Marks for each question are indicated against it.
                        (iii)       Question numbers 1 to 8 are very short-answer questions and carry 1 mark each.
                        (iv)        Question numbers 9 to 18 are short-answer questions and carry 2 marks each.
                        (v)         Question numbers 19 to 27 are also short-answer questions and carry 3 marks
                                    each.
                        (vi)        Question numbers 28 to 30 are long-answer questions and carry 5 marks each.
                        (vii)         Use Log Tables, if necessary. Use of calculators is not allowed.



      /        ~               iffi     *' ~iffi                     <1><W:r ~~U                flF! ~""'     aiiR.m q]ffi ~      ~         I   1
               Write a point of distinction between a metallic solid and an ionic solid other than
               metallic lustre.


               PCI:; afu- PCl ~ -q                  "B ~            ~ <it ~          ~ ~ afu- ~       ?                                         1

               Which one ofPCl ; and PCl ~ is not likely to exist and why?


    ~<§~PI"B                          <1>14'\10')" ~                 if ~<it      - 'J!lm i?                                                    1
               What is the role of graphite in the electrometallurgy of aluminium?


      J.       f'l"lRotf"", ~ 'lit ~
               ~-q~~:~,~,mm-,~I
                                                                         (nucleophilic)       <jI'""1<t>~.m      if ~   ~f"'''''1 <1>-.;2
                                                                                                                                                1
                   Arrange the following compounds in an increasing order of their reactivity in
                   nucleophilic addition reactions: ethanal, prop anal, propanone, butanone.


     J':(J
                   2-iIl'II'Uil&'1-2-31Wr ~                    "<'f>[~     ~   ltifurit
                   Draw the structural formula of 2-methylpr~pan-2-01 molecule .
                                                                                          I          .                                          1




    ./.            f'l"lf<'lf"'''     <fim;"<'f>[     ant.'plt.11".-m. 'IT'! W>ro::                                                             1
                              CH =C-                CH Br
                                    2      I               2
                                          CH3
                   Give the IUP AC name of the following compound.
                              CH =C-                CH Br
                                    2      I               2
                                          CH3

          56/112                                                                          2


\
               ~          3~lg{OI ~         ~       ~lOI~§MCfllCfl{OI   cn1(homopolymerisation) cn1~                             ~                I                        1
 /                 Define the term, 'homopolymerisation'                           giving an example.

     /'            f.,,,,f<'lf,,," 'Iit~~if~~~it>'Ril_if~~:                                                                                                                1
                             CH3NH2, (CH3h NH, (CH3h N ~NH3
                   Arrange the following in the decreasing order of their basic strength in aqueous
                   solutions:



                   ?;I$#tl{1QmfcCfl             ~       (CCI3COOH) ~ ~               1.00 ~       ~            fcfw:R       cn1~                      (1Ct)"ffifT:m
                   fcn<rr~          t-I    fcfw:R CfiT~                 100.18 °C t- I S';I$CR1l{1l{f1lfcCfl ~              ~m           ~~'CflRCfl"

                   cn1~~                    I   (~~mKb=0.512Kkgmol-l)                                                                                                      2
                                                                               ~

                        ctt
                   ~ creJ ~                         W!furt :
                   (i)          ~    ~          (Mole fraction)
                   (ii)         3l1~fllc.lf'"1Cfl fcfw:R (Isotonic solution)
                   (iii)        ~    ~      'CflRCfl"

                   (iv)         ~         fcfw:R

                   A 1.00 molal aqueous solution of trichloroacetic acid (CCI3COOH) is heated to its
                   boiling point. The solution has the boiling point of 100.18 °C. Determine the van't
                   Hoff factor for trichloroacetic acid. (K, for water = 0.512 K kg mor ')

                                                                                OR
               ~e~e the following terms:
             ~/Mole        fraction
             ~       Isotonic solutions
               (iii) Van't Hoff factor
             $Ideal        solution


/:                  ~               -.l\   w "it 'f!I[ Wl>IT ""'"            i?~              « fffiiq;- it>f.,,,,f<'lf,,," ~                            llBI'!if   "it
                   ~ctt~~:
                   (i)          L-I mol s-I
                   (ii)         L mor ' s-I                                                                                                                                2
              pat     do you ~nder:stand by the 'order of a reaction' ? Identify the reaction order
                from each of the following units of reaction rate constant:
              ~           ~-I      mol s-I                                                                                  -:                  ')....
               Ji15             L mor ' s '                                                       ~
                                                                                                      ,&,.l.
                                                                                                                ~\}
                                                                                                                        ~
                                                                                                                                  l.-
                                                                                                                                 \,
                                                                                                                                        I,..-


          56/1/2                                                                     3                                                                               (P.T.O.
    • ~t:1           ~        it ~ """ '<'!'.'<'!' '" ,,<11<1>" fufum: :                                                                                                2
~            ;~     'iH"l41f"1ct ~           ;:}iICffiI~:g ~       -4 NaCI Cl)f ~                   ~               \i'fTctT~ I

             (ii) ~WPm              ~:rr           CfiT~       NaCI ~~                       ~ 'FK q;r ~                 ~~             ~"T.fRT \i'fTctT~ I

             Describe a conspicuous change observed when                                                              "\:;~.
        ~olution                      ofNaCI is added to a sol of hydrated ferric oxide.                                                         ..          _
             ~        beam oflight is passed through a solution ofNaCI and then through a sol.



             Cfll~I~:Sl "EIlB ~ ~                  Cl)f ~      ~            mm ~ ? ~                    "ct'f.:r~           Cl)f    quf.:r ~             ~        rnr
             ~~Cl)f~~\iff~~                                                     I                                                                                       2

       ~What             is meant by coagulation of a colloidal solution ? Describe briefly any three
             methods by which coagulation of lyophobic sols can be carried out.


    13.      f'"it:1F("lf@dl Cl)f quf.:r     ~:                                                                                                                         2

             (i)         Q$'qf1QG       ~ fq~dlQ        ~       -4 ~141~I~co Cfft ~,
             (ii)        -31qR$ct ~            ~    QRtSCf){OI-4 ~     llBT-31ICffiI~:g                 Cfft ~              I

             De~e             the following:
        ~                The role of cryolite in electro metallurgy of aluminium.
             (ii)        The role of carbon monoxide in the refining of crude nickel.



             ~       ~          fq) f'"it:1F("lf@ct Cl)f ~         ~        ~ (i) ~                ~           (ii) ~           ~         (biocatalyst) ?               2

             What is meant by (DA,eptide linka~Ocatalysts                                                     ?


    15.      ~~m~CWUT~~f'"it:1f("lf@ctCfft~~:                                                                                                                           2
             (i)         02   a:ftt   F2 ~         m ~3TI          Cfft ~           -311 rolCfl{OI 31cR2lT3TI
                                                                                       c                    CfiT~                         ~           "Cfl«lT t   ~
                         ~~-402~~F2~                                   I

             (ii)        ~"lR1~                    Cfft ~3TI           Cfft ~               {j41\i1Cflctl ~             ~           ~ ~       Cfft \iff ~         ~ I

                    t
             EXRH:linhe following giving an appropriate reason in each case.
             o           02 and F 2 both stabilize higher oxidation states of metals but 02 exceeds F 2 in
                         doing so.

             (ii)        Structures of Xenon fluorides cannot be explained by Valence Bond approach.

    561112                                                                              4
 16.       f'"1J"""1f~Psh1mH~f'"1Cfl W"iICfl{On CfiT~   ~         :                                                                            2

           (i)      Cr20~- + H+ + 1- ~

           (ii)     MnO~ + NO; + H+ ~

       ~mplete            the following ch~tmiCalequations :

       ~          Lr20~-+H++I-~

       ~r~nO~+NO;+H+~



           f'"1J"""1f~f@ctCSl§wii ell~      QCfl~Cfl CfiT~            ~       ~         :                                                      2
            (i)            6
                    .,I~~I.,
            (ii)    QI<,lIS4Nl.,

           Draw the structure of the monomer for each of the following polymers:
           A    Nylon 6
                                                                                                                        .
              -/                                                                                       fIt.                 ;.. (\/

           y()      Polypropene                                                                        '-     .s
                                                                                                               C   'I




~NA                  it< RNA <t <iR 'f5'< <iN1I"'''' aiw ~                        I <it ~,        ~           it<~,                   if "it
           ~"QCflDNAlf~mmt?                                  ~                                                                                 2

           ~te       the main structural difference between DNA and RNA. Of the two. bases,
            thymine and uracil, which one is present in DNA ?




            ~                            ell
                  286.65 pm ~ 6TfCfiR Wl ~                        ~       ~        ~         ~   Cffi'IT t   I ~             q;r ~
            7.874gcm- 3t  1~~cpf~~~~~CfiTQRCflf~ct~                                                                I

            (Fe q;r "4". ~oq4H     =   55.845 u)                                                                                               3
            Tungsten crystallizes in body centred cubic unit cell. If the edge of the unit cell is
            316.5 pm, what is the radius of tungsten atom?
                                                                 OR
            Iron has a body centred cubic unit cell with a cell dimension of 286.65 pm. The
            density of iron is 7.874 g cm". Use this information to calculate Avogadro's
            number. (At. mass of Fe = 55.845 u)                                      .

  56/1/2                                                              5                                                                   [P.T.O~
 ,,1'    ¥9      h'Fml<l1 (C3HS03)         l1BIT q;f 500 g \;Wf l1BIT            -q- ~             ~       fcwr<R ~            t
                                                                                                                          TT<:rr   I ~

J'       fcwr<R    cpr ~            100.42 °C ~            t~           ¥       \;Wf cpr ~                  100°C     t I P<I1fHI<I1
                                                                                                                                  cit
          rcfi(Rhn;ff   ~   fcwr<R -q- ~           TTt ~   ?                                                                                3

          (Kb \;Wf      ~m   =     0.512 K kg mor ')

          A solution of glycerol (C3Hs03) in water was prepared by dissolving some glycerol
          in 500 g of water. This solution has a boiling point of 100.42 °C while pure water
          boils at 100°C. What mass of glycerol was dissolved to make the solution?
          (Kb for water ~ 0.512 K kg mor")                                      '6~ 2-~  <                            e> ~ ~             Z-::
     /                                                                                                                            ~\O
                                                                                                                          o,~\ ..•...

~R8~
                  2NO(g) + CI2(g) ~ 2 NOCI(g)
          ~m r-"18f("1mtd ~                ~       fcf;<t 'W   I~    l1Tlf1 263 K 1R"           m 'W :
                                                               ~[CI2]                        Cl2   ~~n.tcit~
                wWT~.       ~[NO](M)
                                                                    (M)                                    ~(Mlmin)
                  1                   0.15                          0.15                                      0.60
                  2                   0.15                          0.30                                      1.20
                  3                   0.30                          0.15                                      2.40
                  4                   0.25     -                    0.25                                        ?
          (a)     ~f.:r:p:rcpr~~                      I

          (b)     ~~cprlJHqRCflf("1d~~~~~                                                              I

          (c)     wWT 4 -q- Cl2 ~~~cit~~CFITt?                                                                                                  3

          For the reaction
                  2NO(g) + CI2(g) ~ 2 NOCI(g)

          the following data were collected. All the measurements were taken at 263 K :
            Experiment        I"     1 [NO] (M)            Initial [CI ] (M)                 Initial rate of disappearance
               No.             nitia                                        2                        of Cl2 (M/min)

                   1                   0.15                         0.15                                      0.60
                   2                   0.15                         0.30                                      1.20
                   3                   0.30                         0.15                                      2.40
                   4                   0.25                         0.25                                        ? ~,'l/
          (a)     Write the expression for rate law.                                                          v ,\
          (b)     Calculate the value of rate constant and specify its units.
          (c)     What is the initial rate of disappearance of Cl2 in expo 4 ?

 56/1/2                                                                 6
     22.         ~       Cf;R"UT ~     ~       f'"ilOOifc'1f@dl~
                                                            Cfl1            ~            :                                                                       3
                 (i)     ~       ~             Cfl1
                                                  ~            -q- C02+ ~            ~ Co3+        -q- ,jilcrui~d       m \SfffiT ~   I

                 (ii)    NH3 Cfl13lll~ CO ~~                             ChI~CRlChI~l~~                          I

                 (iii)   Ni(CO)4 CfiT 3l10lrClCh llCflTt Ni(CN)4]2-
                                               3       [                                     *"~ ~~ ~                     I

                 St~     a reason for each of the following                     situations:                                                       0              W
           ~              ~02+       is easily oxidized to         C03+     in presence of a strong ligand.                                       ~          /t;        1:)'
                 (ii)     CO is a stronger complexing                    reagent than NH3.                                                  0 1\             P   ~V\.

           ~The                  molecular            shape ofNi(CO)4           is not the same as that of [Ni(CN)4]2-                             ,0"-


                                                                                                                                                                 3
. y
'/               (i)
                          ~          d-,jiI~c(1iq fc8Im (d4)           *"~       Cr2+ ,jiq'CMCh~~Mn3+                            3qillqCh ~ I

                 (ii)     ~                Cfl1~          l{fCfc.nqs ~           ~            -q- 3q:qq'i ~               ~           cn@       t ~ W'RT
                          ~~~Cfl1~~1

                 (iii)    ~            ~              ~3lT     *"~ ~                 f<wr:R      -q- ~tTT           ~          cn@     t    I

                 ~070uld              you account for the following?

       J                  ~ith       the same d-orbital           configuration              (d4) Cr2+ is a reducing            agent while M~3+
                          is an oxidizing             agent.

           /              The        actinoids          exhibit    a   larger         number           of     oxidation          states         than   the
                          corresponding            members        in the lanthanoid              series.

           \'~            Most of the transition metal ions exhibit characteristic in colours in aqueous
                          solutions,


                              ,&\qimon
                 f'"ilOOifc'1f@d                 *"            f       fufuro:
                                                      mW"lf'"iChll41Ch{OI                    :                                                                   3
                 (i)      'i1~~N.-vti'i cnT ~;:;jjhCh~-q-

                 (ii)     ~           (fflhl~S     cnT 2-~-q-
                 (iii)            cnT
                          Qf'"i<11'i       ~                     -q-
                                                       l{0'Fll~l(1

                 Write chemical equations                    for the following           conversions:
                     \
                 (i)      Nitrobenzene             to benzoic acid.

                 (ii)     Benzyl chloride to 2-phenylethanamip.e.
                 (iii)    Aniline to benzyl alcohol.


     56/1/2                                                                          7

                                                                                                   G
     25.     f'"lC1fMfum
                       ~        t? ~ ~ ~CfiT              ~-~    3~1~{OI
                                                                       ~       :                                   3
              (i)     ~        CfiT<Cf)(Tranquilizers)
              (ii)    WU~              (Food preservatives)
              (iii) ~         3iqql~Cf)(Synthetic detergents)

              What are the following substances? Give one example of each one of them.
           bTranquilizers
           JHJ      Food preservatives
               i.") Synthetic detergents                                                               .


A
•.
      :.      WR f~C1fMf{g(1
              ~
              (i)
                             Q{4»)~I~1 fiT3i1ctm1i(1
                  I ~ l1RCfi""{ ~  cn1 311ctmCf)I{Cf)
                      CH3CH2CH2CH20H
                                      C             ~      ~
                                                   cn1l1BIT ~
                                                              t-           "ill ~ ~      c);-";fIll 3l1r ~
                                                                               1l mrr 1l BTt TIt t- I
                                                                                                             ,~


              (ii)    2-ai9ji!1'ili?1
              (iii)   2-~-1-m~'iIi?1                                                                               3

              Draw the structure and name the product formed if the following alcohols are
              oxidized. Assume that an excess of oxidizing agent is used.
              (i)     CH3CH2CH2CH20H
              (ii)    2-butenol
              (iii)   2-methyl-l-propanol


     27.      ~       ~        ~~~I'i ~                                              (g)~fGCf)
                                                ~ CIffiT qrf t-1l8l ~ ~ ~ ~~~)fl:hfMCf)     ~
              ~3iT            1l~-,                     mm
                                      tffi-f'i~~ICf) t-I ~     ~     lJ:m ~ t- I
              Although chlorine is an electron withdrawing group, yet it is ortho-, para-directing in             '\
              electrophilic aromatic substitution reactions. Explain why it is so ?                                 3




                      (i)      S02; 3l1r cnTur      °-S - °
                      (ii)     elF 3   3l1r cnTur F -   Cl - F

                      (iii)    XeF2     3l1rcnTur   F - Xe - F




     56/1/2                                                       8
               (a)       f.:p:;f {ml'4f1Cfl :g4)Cfl{ofi CfiT~                            ~            :

                             (i)            NaOH               + Cl2        ~
                                      (hot and cone.)

                             (ii)     XeF4 + 02F2 ~                             .
               (b)           f.:p:;f 3lUl31T      ctr fi<iHI~           ~                ~:                       b
                             (i)      H3P02
                                                                                                                                     3
                             (ii)      H2 S207
                             (iii)     XeOF4

               (a)           Complete the following chemical reaction equations:
                             (i)       P 4 + S02Cl2 ~
                             (ii)      XeF6 + H20 ~
                                                                                                                                                                                   '/        ~
               (b)           Predict the shape and the asked angle (900 or more or· less) in each of t e        i
                             following cases:                                                 .          -\.Q.•.O                                                                                 \
                             (i)       S02; and the angle 0-                                 S- 0                                                                       ~\.S   ~o" •.'vJl'b'..{~
                             (ii)      ClF 3 and the angle F - Cl - F                                                                                                              OVIt
                             (iii)     XeF 2 and the angle F - Xe - F
                                                               OR
               (a)7om                  lete the following chemical equations:
                              .        6 NaOH                  + Cl2 ~                   tiJ     c    I; 0" '" Wc,,(                 t
                                       (hot and cone.)                                                        ~

           ~                           XeF4+02F2~
c      ~                 .   '~~aw the structures of the following molecules:
           ~ fi.                       H3P02                                                             b                               @B l'r,~~~L :[?[ffi~ I 0
                         v;:~/:H         S            °                                  \.
                                                                                         0:

                                                                                                         'It                                                                       5    1   z,


                                                                                                                                                 'Er~~;
                     ~               Afr    2     2    7                             ,   S .....-0'''-:-5:
                     ~xeOF4                                                     C.?-/'i-t'                        J   ~'1l




                             -& ~.~                        ~      w;m- ctr ~                         ~?   -& ~                   ~         -q:   mu t.t     0/ ~       CffiYfr~,             D
~                            ~         0/       ctr ~31T                CfiT~                ~       f~<1ICfl{~              CffiYfr~               CfiT~          I
               (b)           ~'{C\q"             ~ ~            -q: ~            ~       ~            -q: Wfffi ~                ~       -q: f.:p:;f ~         mw ~ :
                             Zn(s) + Ag20(s) + H20(!) ~ Zn(;~) + 2 Ag(s) + 2 OH(;)                                                                                                          2,3
                             ~~~mEo                                     ~~G°"Cfll~~                                          I
                             ~        TfCIT: EO Ag+/Ag = +                      0.80V, EO Zn2+/Zn = - 0.76V)



    56/1/2                                                                                                9                                                                            [P.T.O.
 'I        (a)
                     1i1w ~1~Cfl\11 CfiT ~
                     fWt 1i1w ~1~Cfl\11 ~~~
                                                             ~
                                                                     ~
                                                                         ~     01lT&rT ~
                                                                             qRqffi\1   mIDt?
                                                                                                        fcp~    ~       ~        ~     ~             ~


           (b)       0.001 M KCl fcrw:r;r'Cf"fffi ~1~Cfl\11 ~                     298 K If{ 1500 n t 1 ~
                                                                                     Cfjf ~                                                          Cfjf
                     ~Cf:IT         t~            298 K If{ 0.001 M KCI ~ ~II:1Cfl\110.146 x 1O-3S cm!                                     t?
           (a)       What type of a battery is the lead storage battery?                                       Write the anode and the
                     cathode reactions and the overall reaction occurring in a lead storage battery
                     when current is drawn from it.

           (b)       In the button cell, widely used in watches, the following reaction takes place

                     ZnCs) + Ag20Cs) + H20Cl)             ~        ZnC;~) + 2 AgCs) + 2 OHC~)

                     Determine EO and .0.GO for the reaction.



                                                                         OR

      #nefine                     molar conductivity of a solution and explain how molar conductivity
                     changes with change in concentration of solution for a weak and a strong
     ./((            electrolyte.                                           .
      _~         \   !he resistance ofa~onductivity cell cont~ining 0.001 ~ ~Cl solution at 298 K
                                                                                                                                                                          l~
        -            IS 1500 n. What IS the cell constant If the conductivity of 0.001 M KCI
                     solution at 298 K is 0.146 x 1O-3S em"! ?                                                                                                    ~
                                                                                                                                             \ ..L.u(t~               .
                                                                                                                                      Icr--,.---,
                                                                                                                                                IL

/@(a)                              "#
                     f,oP:<if<'lWSl\1   ~ ~         ~ ~             01lT&rT ~           :

                     (i)      ,g4JCflI~'l1I~'S    "# ~ - NH2 ~ t                1~      ~ ~            it ,g41CflI~'5f1., ~ Rmur "#        Bfa:Jf<'l\1
                              mmt      1------.

                     (ii)     BI~cwtlgCR1Yil" ~    l1ffi "# BI(Hl~I~~l"                           ~       t~        2, 4, 6-~-
                              gCR1Yil., ~ ~ Cfl«!T t 1

           (b)       3lUJ~C9HI00~~~~~2,4-DNP~~t,itff.:r~
                     CfiT 3iq~f4\1 Cfl«!T          t~            ~f'"l~{l ~                   Cfl«!T     t 1 om-        dq~4.,       ~ ~      1,     2-
                     ~;:;#J"'SI~CflI¢llfCfJ1f<'lCfl ~~t                  1~~9?1~~                                   1                                       2,3

                                                                         ~

           (a)       f.:rt;r1 ~ ~           ~ fWt     {IB 14f'"lCflfl CfiT ~                  :

                     (i)      ~         ~     ~~~Cfl     ~

                     (ii)     ~~\fl"Hl"       ~     QBI2.1\fll'il.,

  56/1/2                                                                       10
                                                      Hg2+, H2S04
                   (ii)     H3 C - C == C - H -------~)




                            0
                                           1. Cr02Cl2
                   (iii)                                      )
                                           2.    H 30+

                               N02

         (a)       Give a plausible explanation for each one of the following:
                   $        There are two - NH2 groups in semicarbazide. However, only one such
                            group is involved in the formation of semicarbazones.
                   (ii)     Cyclohexanone forms cyanohydrin             in   good   yield   but   2, 4,   6-
                            trimethylcyclohexanone does not.

         (b)       An organic compound with molecular formula C9HlOO forms 2, 4, - DNP
                   derivative, reduces Tollens' reagent and undergoes Cannizzaro's reaction. On
                   vigorous oxidation it -gi:ves-l~2-benzene-di-carboxylic   acid. Identify the
                   compound.


         '~7                chemical tests t~:StinguiSh     between
 Jl ~                     »: Phenol and Benzoic acid
               ~            Be~ophenone     and Acetophenone

         (b)


               v-(i)
                     /0
                   Write the structures of the main products of following reactions:


                              I /
                                /.
                                     + C6HsCOCl
                                                          Anhydrous AlCl3
                                                                  CS2
                                                                              )


                                                      Hg2+, H2S04
                   (ii)     H3 C - C == C - H -------~)




                            0
                                           1. Cr02Cl2
               , (iii)                                         )
                                            2.   H 30+

                               N02




56/1/2                                                       11

				
DOCUMENT INFO
Shared By:
Stats:
views:455
posted:5/8/2012
language:Latin
pages:11
Description: This is the Set 2 of the Chemistry question paper of Class XII CBSE (Central Board of Secondary Education) examinations.