12th Chemistry - Vol.1 Book Back Questions



Latest 12th Standard - English Medium Study Materials Download

12th New Study Materials | Latest Study Notes

I.     12th Full Syllabus - New Study Materials 2022 - 2023




Padasalai’s 12th Chemistry Book Back One Marks


                                               CHEMISTRY BOOKBACK ONE MARKS (MCQs)

                                                        ( BASED ON 2020 EDITION )  

NAME:_________________.                                            CLASS:XII-__.

                                                                                                 UNIT-1  METALLURGY

1.Bauxite has the composition ………………

    (a) Al2O3

(b)    Al2O3.nH2O


    (d) all of these

2.Roasting of sulphide ore gives the gas (A). (A) is a colourless gas. Aqueous solution         

of (A) is acidic. The gas (A) is ………………

(a)    CO2

(b)    SO3

(c)      SO2

(d)    H2S

3.Which one of the following reaction represents calcination?

    (a)2Zn + O2 → 2ZnO

    (b)2ZnS + 3O2 → 2ZnO + 2SO2

    (c)MgCO3 → MgO + CO2    (d) both (a) and (c)

4.The metal oxide which cannot be reduced to metal by carbon is ………………

    (a) PbO

    (b) Al2O3

(c)     ZnO

(e)    FeO

5.Which of the metal is extracted by Hall-Herold process?
   (a) Al
   (b) Ni
   (c) Cu
   (d) ZO

6.Which of the following statements, about the advantage of  roasting of sulphide ore before reduction is not true?       (a) ∆Gf° of sulphide is greater than those for CS2 and H2S.
   (b) ∆Gr° is negative for roasting of sulphide ore to oxide.
   (c) Roasting of the sulphide to its oxide is thermodynamically    feasible.
   (d) Carbon and hydrogen are suitable reducing agents for metal sulphides.
7.Match items in column -1 with the items of column – II and assign the correct code:
Samacheer Kalvi 12th Chemistry Solutions Chapter 1 Metallurgy img-1Samacheer Kalvi 12th Chemistry Solutions Chapter 1 Metallurgy img-2
8.Wolframite ore is separated from tinstone by the process of   ………………
   (a) Smelting
   (b) Calcination
   (c) Roasting
   (d) Electromagnetic separation
9.Which one of the following is not feasible?
   (a) Zn(s) + Cu2+(aq) → Cu(s) + Zn2+(aq)
   (b) Cu(s) + Zn2++(aq) → Zn(s) + Cu2+(aq)
   (c) Cu(s) + 2Ag+(aq) → Ag(s) + Cu2+(aq)
   (d) Fe(s) + Cu2+(aq) → Cu(s) + Fe2+(aq)

10.Electrochemical process is used to extract ………………



     (c) sodium

     (d) Silver

11.Flux is a substance which is used to convert ………………

     (a) Mineral into silicate

     (b) impurities to soluble impurities

     (c) impurities to infusible impurities

(d)  All of these

12.Which one of the following ores is best concentrated by froth – floatation method?

(a)  Magnetite

(b)  Hematite

(c)  Galena

(d)  Cassiterite

13.In the extraction of aluminium from alumina by electrolysis, cryolite is added to ………………

             (a)lower the melting point of alumina

(b)  remove impurities from alumina

            (c)Decrease the electrical conductivity

            (d) increase the rate of reduction

14.Zinc is obtained from ZnO by ………………

(a)  carbon reduction

(b)  reduction using silver

(c)  Electrochemical process

(d)  Acid leaching

15.Extraction of gold and silver involves leaching with cyanide ion.  Silver is later recovered by ………………

(a)  Distillation

             (b) refining

             (c)Displacement with zinc

    (d) liquation

16.Considering Ellingham diagram, which of the following metals can be used to reduce alumina?





17.The following set of reactions are used in refining Zirconium

 this method is known as

(a)  Liquation

       (b)Van Arkel process

(c)Zone refining

(e)  Monds process

18.Which of the following is used for concentrating ore in metallurgy?

       (a) Leaching

       (b) roasting

       (c) froth floatation

       (d) both (a) and (c)

19.The incorrect statement among the following is ………………

   (a) Nickel is refined by Monds process

(b)  Titanium is refined by Van Arkels process

(c)  Zinc blende is concentrated by froth floatation

(d)  In the metallurgy of gold, the metal is leached with dilute sodium chloride solution

20.In the electrolytic refining of copper, which one of the following is used as anode?

    (a) pure copper

    (b) impure copper

    (c) carbon rode

    (d) platinum electrode

21.Which of the following plot gives Ellingham diagram?

a.    ∆S Vs T

b.    ∆G° Vs T

c.     ∆G° Vs

d.    ∆G° Vs T

22.In the Ellingham diagram, for the formation of carbon monoxide

             (a)(△S0△T)is negative

             (b)(△G0△T)is positive

             (c)(△G0△T)is negative

             (d) (△T△G0)is positive, after 700°C, (△G0△T)is negative

23.Which of the following reduction is not thermodynamically feasible?

(a)Cr2O3 → Al2O3 + 2Cr

             (b)Al2O3 → Cr2O3 + 2Al

             (c)3TiO2 + 4Al → 2Al2O3 + 2Al

     (d)None of these

24.Which of the following is not truc with respect to Ellingham diagram?

(a) The energy changes follow a straight line. Deviation occurs when there is a phase change.

(b)  The graph for the formation of CO2 is a straight line almost parallel to free energy axis.

             (c) Negative slope of CO shows that it becomes more stable with increase in temperature.

            (d) Positive slope of metal oxides shows that their stabilities decrease with increase in temperature.


                                                        UNIT-2 : P-BLOCK ELEMENTS-I

1.An aqueous solution of borax is …………

   (a) neutral

   (b) acidic

   (c) basic

   (d) amphoteric

2.Boric acid is an acid because its molecule …………

   (a) contains replaceable H+ ion

   (b) gives up a proton

   (c) combines with proton to form water molecule

   (d) accepts OH– from water, releasing proton.

3.Which among the following is not a borane?

   (a) B2H6

   (b) B3H6

   (c) B4H10

   (d) none of these

4.Which of the following metals has the largest abundance in the earth’s crust?

   (a) Aluminium

   (b) calcium

   (c) Magnesium

   (d) Sodium

5.In diborane, the number of electrons that accounts for banana bonds is …………

   (a) six

   (b) two

   (c) four

   (d) three

6.The element that does not show catenation among the following p-block elements is …………
   (a) Carbon
   (b) silicon
   (c) Lead
   (d) germanium
7.Carbon atoms in fullerene with formula C60 have …………
   (a) sp3 hybridised
   (b) sp hybridised
   (c) sp2 hybridised
   (d) partially sp2 and partially sp3 hybridised
8.Oxidation state of carbon in its hydrides …………
   (a) +4
   (b) -4
   (c) +3
   (d) +2
9.The basic structural unit of silicates is …………
   (a) (SiO3)2-
   (b) (SiO4)2-
   (c) (SiO)
   (d) (SiO4)4-
10.The repeating unit in silicone is …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 2 p-Block Elements - I img-2

11.Which of these is not a monomer for a high molecular mass silicone polymer?

    (a) Me3SiCl

    (b) PhSiCl3

    (c) MeSiCl3

    (d) Me3SiCl3

12.Which of the following is not sp2 hybridised?

    (a) Graphite

    (b) graphene

    (c) Fullerene

    (d) dry ice

13.The geometry at which carbon atom in diamond are bonded to each other is …………

    (a) Tetrahedral

    (b) hexagonal

    (c) Octahedral

    (d) none of these

14.Which of the following statements is not correct?

    (a) Beryl is a cyclic silicate

    (b) Mg2SiO4 is an orthosilicate

    (c) SiO44- is the basic structural unit of silicates

    (d) Feldspar is not aluminosilicate

15.Match items in column – I with the items of column – II ans assign the correct codeassign the correct code

 16.Duralumin is an alloy of …………

     (a) Cu, Mn

     (b) Cu, Al, Mg

     (c) Al, Mn

     (d) Al, Cu, Mn, Mg


17.The compound that is used in nuclear reactors as protective shields and control rods is …………

     (a) Metal borides

     (b) metal oxides

     (c) Metal carbonates

     (d) metal carbide

 18.The stability of +1 oxidation state increases in the sequence …………

    (a) Al < Ga < In < Tl

    (b) Tl < In < Ga < Al

    (c) In < Tl < Ga < Al

    (d) Ga< In < Al < Tl


                                                                    UNIT-3 : P-BLOCK ELEMENTS-II

1.In which of f the ollowing, NH3 is not used?
   (a) Nessler’s reagent
   (b) Reagent for the analysis of IV group basic radical
   (c) Reagent for the analysis of III group basic radical
   (d) Tollen’s reagent
2.Which is time regarding nitrogen?
   (a) least electronegative element
   (b) has low ionisation enthalpy than oxygen
   (c) d-orbitals available
   (d) ability to form pπ – pπ bonds with itself
3.An element belongs to group 15 and 3 rd period of the periodic table, its electronic configuration would be …………
   (a) 1s22s22p4
   (b) 1s22s22p3
   (c) 1s22s22p63s23p2
   (d) 1s22s22p63s23p3
4.Solid (A) reacts with strong aqueous NaOH liberating a foul smelling gas(B) which spontaneously bum in air giving smoky rings. A and B are respectively …………
   (a) P4(red) and PH3
   (b) P4(white) and PH3
   (c) Sand H2S
   (d) P4(white) and H2S
5.On hydrolysis, PCl3 gives …………
   (a) H3PO3
   (b) PH3
   (c) H3PO4
   (d) POOL

6.P4O6 reacts with cold water to give …………

   (a) H3PO3

   (b) H4P2O7

   (c) HPO3

   (d) H3PO4

7.The basicity of pyrophosphorous acid ( H4P2O5) is …………

   (a) 4

   (b) 2

   (c) 3

   (d) 5

8.The molarity of given orthophosphoric acid solution is 2M. its normality is …………

   (a) 6N

   (b) 4N

   (c) 2N

   (d) None of these

9.Assertion – bond dissociation energy of fluorine is greater than chlorine gas

Reason – chlorine has more electronic repulsion than fluorine

   (a) Both assertion and reason are true and reason is the correct explanation of assertion.

   (b) Both assertion and reason are true but reason is not the correct explanation of assertion.

   (c) Assertion is true but reason is false.

   (d) assertion and reason are false.

10.Among the following, which is the strongest oxidizing agent?

   (a) Cl2

   (b) F2

   (c) Br2

   (d) I2

11.The correct order of the thermal stability of hydrogen halide is …………

   (a) HI > HBr > HCl > HF

   (b) HF > HCl > HBr > HI

   (c) HCl > HF > HBr > HI

   (d) HI > HCl > HF > HBr

12.Which one of the following compounds is not formed?

    (a) XeOF4

    (b) XeO3

    (c) XeF2

    (d) NeF2

13.Most easily liquefiable gas is …………

    (a) Ar

    (b) Ne

    (c) He

    (d) Kr

14.XeF6 on complete hydrolysis produces …………

    (a) XeOF4

    (b) XeO2F4

    (c) XeO3

    (d) XeO2

15.Which of the following is strongest acid among all?

    (a) HI

    (b) HF

    (c) HBr

    (d) HCl

16.Which one of the following orders is correct for the bond dissociation enthalpy of halogen molecules?

    (a) Br2 > I2 > F2 > Cl2

    (b) F2 > Cl2 > Br2 > I2

    (c) I2 > Br2 > Cl2 > F2

    (d) Cl2 > Br2 > F2 > I2

17.Among the following the correct order of acidity is …………

    (a) HClO2 < HCIO < HClO3 < HClO4

    (b) HClO4 < HClO2 < HCIO < HClO3

    (c) HClO3 < HClO4 < HClO2 < HCIO

    (d) HCIO < HClO2 < HClO3 < HClO4

18.When copper is heated with cone HNO3 it produces …………

    (a) CU(NO3)2 , NO and NO2

    (b) Cu(NO3)2 and N2O

   (c) CU(NO3)2 and NO2

   (d) Cu(NO3)2 and NO


                                      UNIT-4 : TRANSITION & INNER TRANSITION ELEMENTS

1.Sc ( Z=21) is a transition element but Zinc (z=30) is not because ……………..

   (a) both Sc3+ and Zn2+ ions are colourless and form white compounds.

   (b) in case of Sc, 3d orbital are partially filled but in Zn these are completely filled

   (c) last electron as assumed to be added to 4s level in case of zinc

   (d) both Sc and Zn do not exhibit variable oxidation states

2.Which of the following d block element has half filled penultimate d sub shell as well as half filled valence sub shell?

   (a) Cr

   (b) Pd

   (c) Pt

   (d) none of these

3.Among the transition metals of 3d series, the one that has highest negative (M2+/ M) standard electrode potential is ……………..

    (a) Ti

    (b) Cu

    (c) Mn

    (d) Zn

4.Which one of the following ions has the same number of unpaired electrons as present in V3+?

    (a) Ti3+

    (b) Fe3+

    (c) Ni2+

    (d) Cr3+

5.The magnetic moment of Mn2+ ion is ……………..

    (a) 5.92BM

    (b) 2.80BM

    (c) 8.95BM

    (d) 3.90BM

6.The catalytic behaviour of transition metals and their compounds is ascribed mainly due to ……………..

    (a) their magnetic behaviour

    (b) their unfilled d orbitals

    (c) their ability to adopt variable oxidation states

(d)  their chemical reactivity

7.The correct order of increasing oxidizing power in the series ……………..

    (a) VO+2 < Cr2O2−7 < MnO–4

    (b) Cr2O2−7 < VO+2 < MnO–4

    (c) Cr2O2−7 < MnO–4 < VO+2

    (d) MnO–4 < Cr2O2−7 < VO+2

8.In acid medium, potassium permanganate oxidizes oxalic acid to ……………..
   (a) Oxalate
   (b) Carbon dioxide
   (c) acetate
   (d) acetic acid
9.Which of the following statements is not true?
   (a) on passing H2S, through acidified K2Cr2O7 solution, a milky colour is observed.
   (b) Na2Cr2O7 is preferred over K2Cr2O7 in volumetric analysis
   (c) K2Cr2O7 solution in acidic medium is orange in colour
   (d) K2Cr2O7 solution becomes yellow on increasing the pH beyond 7
10.Permanganate ion changes to in acidic medium ……………..
   (b) Mn2+
   (c) Mn3+
   (d) MnO2

11.A white crystalline salt (A) react with dilute HCl to liberate a suffocating gas (B) and also forms a yellow precipitate . The gas (B) turns potassium dichromate acidified with dil H2SO4 to a green coloured solution(C). A,B and C are respectively ……………..
   (a) Na2SO3, SO2, Cr2(SO4)3
   (b) Na2S2O3, SO2, Cr2(SO4)3
   (c) Na2S, SO2, Cr2(SO4)3
   (d) Na2SO4, SO2, Cr2(SO4)3

12.The number of moles of acidified KMnO4 required to oxidize 1 mole of ferrous oxalate(FeC2O4) is …………..
   (a) 5
   (b) 3
   (c) 0.6
   (d) 1.5
13.Which one of the following statements related to lanthanons is incorrect?
   (a) Europium shows +2 oxidation state.
   (b) The basicity decreases as the ionic radius decreases from Pr to Lu.
   (c) All the lanthanons are much more reactive than aluminium.
   (d) Ce4+ solutions are widely used as oxidising agents in volumetric analysis.
14.Which of the following lanthanoid ions is diamagnetic?
   (a) Eu2+
   (b) Yb2+
   (c) Ce2+
   (d) Sm2+

15.Which of the following oxidation states is most common among the lanthanoids?
   (a) 4
   (b) 2
   (c) 5
   (d) 3
16.Assertion: Ce4+ is used as an oxidizing agent in volumetric analysis.
Reason: Ce4+ has the tendency of attaining +3 oxidation state.

  (a) Both assertion and reason are true and reason is the correct explanation of assertion.

  (b) Both assertion and reason are true but reason is not the correct explanation of assertion.

  (c) Assertion is true but reason is false. .

  (d) Both assertion and reason are false.

17.The most common oxidation state of actinoids is ……………

   (a) +2

   (b) +3

   (c) +4

   (d) +6

18.The actinoid elements which show the highest oxidation state of +7 are ……………

  (a) Np, Pu, Am

  (b) U, Fm, Th

  (c) U, Th, Md

  (d) Es, No, Lr

19.Which one of the following is not correct?

  (a) La(OH)2 is less basic than Lu(OH)3

  (b) In lanthanoid series ionic radius of Ln3+ ions decreases

  (c) La is actually an element of transition metal series rather than lanthanide series

  (d) Atomic radii of Zr and Hf are same because of lanthanide contraction


                                                UNIT-5 : COORDINATION CHEMISTRY

 1.The sum of primary valance and secondary valance of the metal M in the complex [M(en)2(Ox)]Cl is ……………..

   (a) 3

   (b) 6

   (c) -3

(d)  9

2.An excess of silver nitrate is added to 100ml of a 0.01M solution of penta aquachlorido chromium (III) chloride. The number of moles of AgCl precipitated would be ……………..

   (a) 0.02

   (b) 0.002

   (c) 0.01

   (d) 0.2

3.A complex has a molecular formula MSO4Cl. 6H2O. The aqueous solution of it gives white precipitate with Barium chloride solution and no precipitate is obtained when it is treated with silver nitrate solution. If the secondary valence of the metal is six, which one of the following correctly represents the complex?

   (a) [M(H2O)4Cl] SO2. 2H22O

   (b) [M(H2O)6] SO4

   (c)[M(H2O)5Cl] SO4. H2O

   (d) [M(H2O)3Cl] SO4. 3H2O

4.Oxidation state of Iron and the charge on the ligand NO in [Fe(H2O)5NO] SO4 are ……………..

   (a) +2 and 0 respectively

   (b) +3 and 0 respectively

   (c) +3 and -1 respectively

  (d) +1 and +1 respectively

5.As per IUPAC guidelines, the name of the complex [CO(en)2(ONO)Cl]Cl is ……………..

(a)  Chlorobisethylenediaminenitritocobalt (III) chloride

(b)  chloridobis (ethane-1, 2-diamine) nitro k – Ocobaltate (III) chloride

(c)   chloridobis (ethane-1, 2-diammine) nitrito k – Ocobalt (II) chloride

     (d) chloridobis (ethane-1, 2-diamine) nitro k – Ocobalt (III) chloride

 6.IUPAC name of the complex K3[Al(C2O4)3] is ……………..

   (a) potassiumtrioxalatoaluminium (III)

   (b) potassiumtrioxalatoaluminate (II)

  (c) potassiumtrisoxalatoaluminate (III)

  (d) potassiumtrioxalatoaluminate (III)

7.A magnetic moment of 1.73BM will be shown by one among the following ……………..

  (a) TiCl4

  (b) [COCl6]4-

  (c) [Cu(NH3)4]2+

  (d) [Ni(CN)4]2-

8.Crystal field stabilization energy for high spin d5 octahedral complex is ……………..

  (a) – 0.6∆0

  (b) 0

  (c) 2 (P – ∆0)

  (d) 2 (P + ∆0)

9.In which of the following coordination entities the magnitude of ∆0 will be maximum?

  (a) [CO(CN)6]3-

  (b) [CO(C2O4)3]3-

  (c) [CO(H2O)6]3+


10.Which one of the following will give a pair of enantiomorphs?

  (a) [Cr(NH3)6][CO(CN)6]

  (b) [CO(en)2Cl2]Cl

  (c) [Pt(NH3)4][PtCl4]


11.Which type of isomerism is exhibited by [Pt(NH3)2Cl2] ?

  (a) Coordination isomerism

  (b) Linkage isomerism

  (c) Optical isomerism

(d)  Geometrical isomerism

12.How many geometrical isomers are possible for [ Pt (Py) (NH3) (Br) (Cl) ]?

  (a) 3

  (b) 4



13.Which one of the following pairs represents linkage isomers?

  (a) [Cu(NH3)4] [PtCl4] and [Pt(NH3)4] [CuCl4]

  (b) [CO(NH3)5(NO3)]SO4 and [CO(NH3)5(ONO)]

  (c) [CO(NH3)4(NCS)2]Cl and [CO(NH3)4(SCN)2]Cl

(b)  both (b) and (c)

14.Which kind of isomerism is possible for a complex [CO(NH3)4Br2]Cl ?

  (a) geometrical and ionization

  (b) geometrical and optical

  (c) optical and ionization

  (d) geometrical only

15.Which one of the following complexes is not expected to exhibit isomerism?

  (a) [Ni(NH3)4(H2O)2]2+

  (b) [Pt(NH3)2 Cl2]

  (c) [CO(NH3)5SO4]Cl

  (d) [Fe(en)3]3+

16.A complex in which the oxidation number of the metal is zero is ……………..

  (a) K4[Fe(CN)6]

  (b) [Fe(CN)3(NH3)3]

  (c) [Fe(CO)5]

  (d) both (b) and (c)

17.Formula of tris (ethane-1, 2-diamine) iron (II) phosphate ……………..

  (a) [Fe(CH3 – CH(NH2)2)3] (PO4)3

  (b) [Fe(H2N – CH2 – CH2 – NH2)3] (PO4)

  (c) [Fe(H2N – CH2 – CH2 – NH2)3](PO4)2

  (d) [Fe(H2N – CH2 – CH2 – NH2)3](PO4)2

18.Which of the following is paramagnetic in nature?

  (a) [Zn(NH3)4]2+

  (b) [CO(NH3)6]3+

  (c) [Ni(H2O)6]2+

  (d) [Ni(CN)4]2-

19.Facmer isomerism is shown by ……………..

  (a) [CO(en)3]3+

  (b) [CO(NH3)4(Cl)2]+

  (c) [CO(NH3)3(Cl)3]

  (d) [CO(NH3)5Cl]SO4

20.Choose the correct statement.

  (a) Square planar complexes are more stable than octahedral complexes

  (b) The spin only magnetic moment of [Cu(Cl)4]2- is 1.732 BM and it has square planar structure.

  (c) Crystal field splitting energy (Δ0) of [FeF6]4- is higher than the (Δ0) of [Fe(CN)6]4-

  (d) crystal field stabilization energy of [V(H2O)6]2+ is higher than the crystal field stabilization of [Ti(H2O)6]2+


                                                                       UNIT-6 : SOLID STATE

1.Graphite and diamond are ………..
  (a) Covalent and molecular crystals
  (b) ionic and covalent
  (c) both covalent crystals
  (d) both molecular crystals
 2.An ionic compound ABy crystallizes in fee type crystal structure with B ions at the centre of each face and A ion occupying centre of the cube, the correct formula of A B is ………..
  (a) AB
  (b) AB3
  (c) A3B
  (d) A8B6
3.The ratio of close packed atoms to tetrahedral hole in cubic packing is ………..
   (a) 1:1.                         

   (b) 1:2
   (c). 2:1                         

   (d) 1:4

4.Solid CO2 is an example of ………..
   (a) Covalent solid
   (b) metallic solid
   (c) molecular solid
   (d) ionic solid
5.Assertion: monoclinic sulphur is an example of monoclinic crystal system.
Reason: for a monoclinic system, a 
 b  c and α = γ = 90° , β  90°.
    (a) Both assertion and reason are true and reason is the correct explanation of assertion.
    (b) Both assertion and reason are true but reason is not the correct explanation of assertion.
    (c) Assertion is true but reason is false.
    (d) Both assertion and reason are false.
6.In calcium fluoride, having the flurite structure the coordination number of Ca2+ ion and F Ion are ………..
   (a) 4 and 2
   (b) 6 and 6
   (c) 8 and 4
   (d) 4 and 8
7.The number of unit cells in 8gm of an element X (atomic mass 40) which crystallizes in bcc pattern is (NA is the Avogadro number)
   (a) 6.023 x 1023
   (b) 6.023 x 1022
   (c) 60.23 x 1023
8.In a solid atom M occupies ccp lattice and 
(13) of tetrahedral voids are occupied by atom N. Find the formula of solid formed by M and N.
   (a) MN
   (b) M3N
   (C) MN3
   (d) M3N2
9.The ionic radii of A+ and B are 0.98 x 10-10 m and 1.81 x 10-10 m , the coordination number of each ion in AB is ………..
   (a) 8
   (b) 2
   (c) 6
   (d) 4
 10.CaCl has bcc arrangement, its unit cell edge length is 400pm, its inter atomic distance is ………..
   (a) 400pm
   (b) 800pm
g3–√ x 100pm
(32) x 400 pm
11.A solid compound XY has NaCl structure, if the radius of the cation is 100pm , the radius of the anion will be ………..
   (c) 100 x 0.414

12.The vacant space in bcc lattice unit cell is ………..
   (a) 48%
   (b) 23%
   (c) 32%
   (d) 26%
13.The radius of an atom is 300pm, if it crystallizes in a face centered cubic lattice, the length of the edge of the unit cell is ………..
   (a) 488.5pm
   (b) 848.5pm
   (c) 884.5pm
   (d) 484.5pm
14.The fraction of total volume occupied by the atoms in a simple cubic is ………..
15.The yellow colour in NaCl crystal is due to ………..
   (a) excitation of electrons in F centers
   (b) reflection of light from Cl ion on the surface
   (c) refraction of light from Na+ ion
   (d) all of the above
16.If ’a’ stands for the edge length of the cubic system; sc ,bcc, and fcc. Then the ratio of radii of spheres in these systems wilL be respectively.
Samacheer Kalvi 12th Chemistry Solution Chapter 6 Solid State-3
17.If a is the length of the side of the cube, the distance between the body centered atom and one comer atom in the cube will be ………..
18.Potassium has a bcc structure with nearest neighbor distance 4.52 A. its atomic weight is 39. Its density will be ………..
   (a) 915 kg m-3
   (b) 2142 kg m-3
   (c) 452 kg m-3
   (d) 390 kg m-3
19.Schottky defect in a crystal is observed when ………..
   (a) unequal number of anions and anions are missing from the lattice
  (b) equal number of anions and anions are missing from the lattice
   (c) an ion leaves its normal site and occupies an interstitial site
  (d) no ion is missing from its lattice.
20.The cation leaves its normal position in the crystal and moves to some interstitial position, the defect in the crystal is known as ………..
  (a) Schottky defect
  (b) F center
  (c) Frenkel defect
  (d) non-stoichiometric defect
21.Assertion – due to Frenkel defect, density of the crystalline solid decreases.
Reason – in Frenkel defect cation and anion leaves the crystal.
  (a) Both assertion and reason are true and reason is the correct explanation of assertion.
  (b) Both assertion and reason are true but reason is not the correct explanation of assertion.
  (c) Assertion is true but reason is false.
  (d) Both assertion and reason are false
22.The crystal with a metal deficiency defect is ………..
  (a) NaCI
  (b) FeO
  (c) ZnO
  (d) KCI
23. Two dimensional solid pattern formed by two different atoms X and Y is shown below. The black and white squares represent atoms X and Y respectively. The simplest formula for the compound based on the unit cell from the pattern is ………..
Samacheer Kalvi 12th Chemistry Solution Chapter 6 Solid State-6
   (a) XY8
   (b) X4Y9
   (c) XY2
   (d) XY4
                                               UNIT-7 : CHEMICAL KINETICS

1.For a first order reaction A → B the rate constant is x min-1. If the initial concentration of A is 0.01 M, the concentration of A after one hour is given by the expression.
   (a) 0.01 e-x
   (b) 1 x 10-2 (1 – e-60x)
   (c) (1 x 10-2) e-60x
   (d) none of these
2.A zero order reaction X → Product, with an initial concentration 0.02M has a half life of 10 min. If one starts with concentration 0.04M, then the half life is …………….
   (a) 10 s
   (b) 5 min
   (c) 20 min
   (d) cannot be predicted using the given information
3.Among the following graphs showing variation of rate constant with temperature (T) for a reaction, the one that exhibits Arrhenius behavior over the entire temperature range is ……………
Samacheer Kalvi 12th Chemistry Solutions Chapter 7 Chemical Kinetics-3
4.For a first order react ion A → product with initial concentration x mol L-1, has a half life period of 2.5 hours. For the same reaction with initial concentration mol L-1 the half life is
   (a) (2.5 x 2) hours
(2.52) hours
   (c) 2.5 hours
   (d) Without knowing the rate constant, t1/2 cannot be determined from the given data
5.For the reaction, 2NH3 → N2 + 3H2, if
Samacheer Kalvi 12th Chemistry Solutions Chapter 7 Chemical Kinetics-6
then the relation between
k1, k2 and k3 is
   (a) k1 = k2 = k3
   (b) k1 = 3 k2 = 2 k3
   (c) 1.5k1 = 3 k2 = k3
   (d) 2k1 = k2 = 3 k3
6.The decomposition of phosphine (PH3) on tungsten at low pressure is a first order reaction. It is because the …………….
    (a) rate is proportional to the surface coverage
    (b) rate is inversely proportional to the surface coverage
    (c) rate is independent of the surface coverage
    (d) rate of decomposition is slow
7.For a reaction Rate = k [acetone]3/2 then unit of rate constant and rate of reaction respectively is …………..
   (a) (mol L-1 s-1), (mol-1/2 L1/2 s-1)
   (b) (mol-1/2 L1/2 s-1), (mol L-1 s-1)
   (c) (mol1/2 L1/2 s-1), (mol L-1 s-1)
   (d) (mol L s-1), (mol1/2 L1/2 s)
8.The addition of a catalyst during a chemical reaction alters which of the following quantities?
   (a) Enthalpy
   (b) Activation energy
   (c) Entropy
   (d) Internal energy
9.Consider the following statements:
(i) increase in the concentration of the reactant increases the rate of a zero-order reaction.
(ii) rate constant k is equal to collision frequency A if Ea = o
(iii) rate constant k is equal to collision frequency A if Ea = o
(iv) a plot of ln (k) vs T is a straight line.
(v) a plot of In (k) vs 
(1T) is a straight line with a positive slope.

Correct statements are
   (a) (ii) only
   (b) (ii) and (iv)
   (c) (ii) and (v)
   (d) (i), (ii) and (v)
10.In a reversible reaction, the enthalpy change and the activation energy in the forward direction are respectively – x kJ mol-1 and y kJ mol-1. Therefore, the energy of activation in the backward direction is ………..
   (a) (v – x)kJ mol-1
   (b) (x + y) J mol-1
   (c) (x – y) kJ mol-1
   (d) (x + y) x 103 J mol-1
11.What is the activation energy for a reaction if its rate doubles when the temperature is raised from 200K to 400K? (R 8.314 JK-1 mol-1)
   (a) 234.65 kJ mol-1 K-1
   (b) 434.65 kJ mol-1 K-1
   (c) 434.65 J mol-1 K-1
   (d) 334.65 J mol-1 K-1
Samacheer Kalvi 12th Chemistry Solutions Chapter 7 Chemical Kinetics-11
This reaction follows first order kinetics. The rate constant at particular temperature is 2.303 x 102 hourd. The initial concentration of cyclopropane is 0.25 M. What will be the concentration of cyclopropane after 1806 minutes? (Log 2 = 0.30 10)
    (a) 0.125 M
    (b) 0.215 M
    (c) 0.25 x 2.303 M
    (d) 0.05 M

13.For a first-order reaction, the rate constant is 6.909 min-1. The time taken for 75% conversion in minutes is …………
(32) log 2
(32) log 2
(32) log (34)
(23) log (43)
14.In a first-order reaction x → y; if k is the rate constant and the initial concentration of the reactant x is 0.1 M, then, the half-life is ……..
   (d) none of these
15.Predict the rate law of the following reaction based on the data given below:
2A + B → C + 3D
Samacheer Kalvi 12th Chemistry Solutions Chapter 7 Chemical Kinetics-15
   (a) rate = k [A]2 [B]
   (b) rate = k [A][B]2
   (c) rate = k [A][B]
   (d) rate = k [A]1/2 [B]3/2
16.Assertion: rate of reaction doubles when the concentration of the reactant is doubled if it is a first-order reaction.
Reason: rate constant also doubles
   (a) Both assertion and reason are true and reason is the correct explanation of assertion.
   (b) Both assertion and reason are true but reason is not the correct explanation of assertion.
   (c) Assertion is true but reason is false.
   (d) Both assertion and reason are false.
17.The rate constant of a reaction is 5.8 x 102 s1. The order of the reaction is ………….
   (a) First order
   (b) zero-order
   (c) Second-order
   (d) Third order
18.For the reaction, N2 O5(g) → 2NO2(g) +
12 – O2(g) the value of the rate of disappearance of N2O5 is given as 6.5 x 10-2 mol L-1s-1 The rate of formation of NO2 and O2 is given respectively as …………….
   (a) (3.25 x 10-2 mol L-1s-1) and (1.3 x 10-2 mol L-1s-1)
   (b) (1.3 x 10-2 mol L-1s-1) and (3.25 x 102 mol L-1s-1)
   (c) (1.3 x 10-1 mol L-1s-1) and (3.25 x 10-2 mol L-1s-1)
    (d) None of these
19.During the decomposition of H2O2 to give dioxygen, 48g O2 is formed per minute at a certain point in time. The rate of formation of water at this point is …………….
   (a) 0.75 mol min-1
   (b) 1.5 mol min-1
   (c) 2.25 mol min-1
   (d) 3.0 mol min-1
20.If the initial concentration of the reactant is doubled, the time for half-reaction is also doubled. Then the order of the reaction is …………
   (a) Zero
   (b) one
   (c) Fraction
   (d) none
21.In a homogeneous reaction A ? B + C + D, the initial pressure was P0 and after time t it was P. Expression for rate constant in terms of P0, P and t will be ……….
Samacheer Kalvi 12th Chemistry Solutions Chapter 7 Chemical Kinetics-21
22.If 75% of a first-order reaction was completed in 60 minutes, 50% of the same reaction under the same conditions would be completed in ………
   (a) 20 minutes
   (b) 30 minutes
   (c) 35 minutes
   (d) 75 minutes
23.The half-life period of a radioactive element is 140 days. After 560 days, 1 g of the element will be reduced to
12 g
14 g
18 g
116 g
 24.The correct difference between first and second-order reactions is that …………

   (a) A first-order reaction can be catalysed a second-order reaction cannot be catalysed.

   (b) The half-life of a first-order reaction does not depend on [A0] the half-life of a second-order reaction does depend on [A0].

   (c) The rate of a first-order reaction does not depend on reactant concentrations; the rate of a second-order reaction does depend on reactant concentrations.

   (d) The rate of a first-order reaction does depend on reactant concentrations; the rate of a second-order reaction does not depend on reactant concentrations.

25.After 2 hours, a radioactive substance becomes (116)th of original amount. Then the half life (in mm) is ………………

   (a) 60 minutes

   (b) 120 minutes

   (c) 30 minutes

   (d) 15 minutes




Post a Comment

Dear Reader,

Enter Your Comments Here...

Recent Posts


Total Pageviews

Blog Archive