JEE Main Previous Year Papers Questions With Solutions Chemistry Elements of d-Block,f-Block and Complexes

JEE Main Previous Year Papers Questions With Solutions Chemistry  Elements of  d-Block,f-Block and Complexes

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-1
Ans.(2) A square planer complex is formed by hybridisation of s, px, py and dx2 -dy2 atomic orbitals.

2.The type of isomerism present in nitro- pentamine chromium (III) chloride is (2002)
(1)optical          2)   linkage
3) ionization    4)   polymerisation
Ans.(2) The nitro group can attach to metal through nitrogen as (-N02) or through oxygen as nitrito (-ONO).

3.CH3-Mg-Br is an organo metallic compound due to  (2002)
(1)Mg-Br bond      2)   C-Mg bond
3) C-Br bond         4)   C-H bond
Ans.(2)Bond between C atom of organic molecule and metal atom.

4.Most common oxidation states of Ce (cerium) are     (2002)
(1)+2, + 3         2)   +2, + 4
3) +3, + 4       4)   +3, +5
Ans.(4)Common oxidation states of Ce(Cerium) are +3 and + 4.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-5

5.Arrange Ce+3, La+3, Pm+3 and Yb+3 in increasing order of their ionic radii (2002)
(1)Yb+3 < Pm+3 < Ce+3 < La+3
(2)Ce+3 < Yb+3 < Pm+3 < La+3
(3)Yb+3 < Pm+3 < La+3 < Ce+3
(4)Pm+3 < La+3 < Ce+3 < Yb+3
Ans.(1) According to their positions in the periods, these values are in the order :

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-6
Ans.(2) A more basic ligand forms stable bond with metal ion, Cl– is most basic amongst all.

7.Ammonia forms the complex ion [Cu(NH3)4]2+with copper ions in alkaline solutions but not in acidic solutions. What is the reason for it ? (2003)
(1)In acidic solutions protons coordinate with ammonia molecules forming NH4 ions and NH3 molecules are not available
(2)In alkaline solutions insoluble Cu(OH)2 is precipitated which is soluble in excess of any alkali.
(3)Copper hydroxide is an amphoteric substance
(4)In acidic solutions hydration protects copper ions
Ans.(1) Cu2+ forms complex with free NHy (4)

8.One mole of the complex compound Co(NH3)5C13, gives 3 moles of ions on dissolution in water. One mole of the same complex reacts with two moles of AgN03 solution to yield two moles of AgCl(s). The structure of the complex is          (2003)
(1)[Co(NH3)3Cl3].2NH3
(2)[Co(NH3)4C12]C1.NH3
(3)[Co(NH3)4C1]C12.NH3 4) [Co(NH3)5C1]C12
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-8

9.In the coordination compound, K4[Ni(CN)4], the oxidation state of nickel is             (2003)
1)0  2) + 1          3) + 2           4) – l
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-9

10.A reduction in atomic size with increase in atomic number is a characteristic of elements of          (2003)
(1)d-block 2) f-block
3) radioactive series 4) high atomic masses
Ans.(2) f-block elements show a regular decrease in atomic size due to lanthanide/actinide contraction.

11.The coordination number of central metal atom in a complex is determined by (2004)
(1)The number of ligands around a metal ion bonded by sigma bonds
(2)The number of only anionic ligands bonded to the metal ion
(3)The number of ligands around a metal ion bonded by sigma and pi- bonds both
(4)The number of ligands around a metal ion bonded by pi-bonds
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-11

12.Which one of the following complexes in an outer orbital complex ?      (2004)
(1)[Fe(CN)6]4–              2) [Ni(NH3)6]2+
3) [Co(NH3)6]3+             4) [Mn(CN)6]4_
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-12

13.Coordination compound have great importance in biological systems. In this context which of the following statements is incorrect ?     (2004)
‘ 1) Chlorophylls are green pigments in plants and contains calcium
(2)Carboxypeptidase – A is an enzyme and contains zinc
(3)Cyanocobalamin is B12 and contains cobalt
(4)Haemoglobin is the red pigment of blood and  contains iron
Ans.(3)Chlorophyll contains magnesium instead of calcium.

14.Cerium(Z=58)is an important member of the lanthanoids. Which of the following statements about cerium is incorrect ? (2004)
(1)The common oxidation states of cerium are +3 and +4
(2)Cerium (IV) acts as an oxidizing agent
(3)The +4 oxidation state of cerium is not knownin solutions                                        .
(4)The +3 oxidation state of cerium is more stable than the +4 oxidation state
Ans.(3) Oxidation potential of Ce(IV) in aqueous solution is supposed to be -ve i.e. -0.784 V at 25°C.

15.Which one the following has largest number of isomers? (R-= alkyl group, en = ethylenediamine) (2004)
1) [Ru(NH3)4C12+]      2)         [Co(en)2Cl2]+
3) [Ir(PR3)2 H(CO)]2+      4)   [Co(NH3)5C1]2+
Ans.(2)Geomerical and optical isomerisum.

16.The correct order of magnetic moments (spin only values in B.M.) among is               (2004)
(1)[MnClJ2- > [CoCl4]-2 > [Fe(CN)6r
(2)[Fe(CN)6]’4 > [CoClJ2– > [MnClJ2-
(3)[Fe(CN)J4- > [MnClJ2– > [CoClJ2-
(4)[MnClJ2- > [Fe(CN)J4– > [CoClJ2-
Ans.(1) Number of unpaired e” in Mn2+ is 5, Co2+ is 3 and Fe2+ is zero.

17.The oxidation state of  Cr in  the complex[Cr(NH3)4Cl2]+ is  (2005)
(1)+3     2) +2           3) +1           4)0
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-17

18.Calomel (Hg2Cl2) on reaction with ammonium hydroxide gives                                    (2005)
(1)HgNH2Cl       2)   NH2-Hg-Hg-Cl
3) Hg20                  4)    HgO
Ans.(1) Reaction between calomel and ammonia is Hg2Cl2 + 2NH4OH ->Hg + Hg(NH2 )C1 + 2H2

19.The IUPAC name of the coordination compound K3[Fe(CN)6] is     (2005)
(1)Potassium hexacyanoferrate (II)
(2)Potassium hexacyanoferrate (III)
(3)Potassium hexacyanoiron (II)
(4)tripotassium hexcyanoiron (II)
Ans.(2) Complex of Fe3+ is ferrate(III).

20.Which of the following compounds shows optical isomerism?     (2005)
1) [Cu(NH3)4]+2               2)    [ZnClJ-2
3) [Cr(C204)3]-3                4)    [Co(CN)6]-3
Ans.(3) The optical isomers are.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-20

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-21
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-21 (2)

22.The value of the ‘spin only’ magnetic moment for one of the following configurations is 2.84 BM. The correct one is       (2005)
(1)d4 (in strong ligand filed)
(2)d4 (in weak ligand field)
(3)d3 (in weak as well as in strong fields)
(4)d5 (in strong ligand field)
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-22 (2)

23.The IUPAC name for the complex [Co(N02)(NH3)5]C12 is (2006)
(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
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-23

24.Nickel (Z = 28) combines with a uninegative monodentate ligand X~ to form a paramagnetic complex [NiXJ2-. The number of unpaired electron(s) in the nickel and geometry of this complex ion are, respectively       (2006)
(1)one, tetrahedral      2) two, tetrahedral
3) one, square planar   4) two, square planar
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-24

25.In Fe(CO)5, the Fe-C bond possesses (2006)
(1)k -character only
(2)both 0 and n characters
(3)ionic character 4) a -character only…
Ans.(2) Because of back bonding both o and kbonds are present.

26.How many EDTA (ethylenediaminetetraacetic acid) molecules are required to make an octahedral complex with a Ca2+ ion ? (2006)
(1)Six 2) Three 3) One 4) Two
Ans.(3) EDTA4- is hexadentate ligand.

27.Lanthanoid contraction is caused due to (2006)
(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
Ans.(4) Poor slidding by f-electrons.

28.Identify the incorrect statement among the, following                                                (2007)
(1)d-Block elements show irregular and erratic chemical properties among themselves
(2)La and Lu have partially filled d orbitals and no other partially filled orbitals
(3)The chemistry of various lanthanoids is very similar
(4)4f and 5f orbitals are equally shielded
Ans.(4) 4f and 5f belongs to different energy levels, hence the shielding effect is on them is not the same. Shielding of 4f is more than 5f.

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-29

Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-29
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-29-1

30.The actinoids exhibits more number of oxida­tion states in general than the lanthanoids. This is because          (2007)
(1)The 5f orbitals are more buried than the 4f orbitals
(2)There is a similarity between 4f and 5f orbit­als in their angular part of the wave function
(3)The actinoids are more reactive than the lanthanoids
(4)The 5f orbitals extend further from the nucleus than the 4f orbitals

Ans.(4) The actinoids exhibit more number of oxi­dation states in general than the lanthanoids. This is because the 5f orbitals extend further from the nucleus than the 4f orbitals.

31.The coordination number and the oxidation state of the element ‘E’ in the complex [E(en)2(C204)]N02 (where ‘en’ is ethylene diamine) are, respectively,   (2008)
1) 6 and 2 2) 4 and 2 3) 4 and 3 4) 6 and 3

Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-31

32.Larger number of oxidation states are exhibited by the actinoids than those by the lanthanoids, the main reason being (2008)
(1)4f orbitals more diffused than the 5f orbitals
(2)Lesser energy difference between 5f and 6d than between 4f and 5d orbitals
(3)More energy difference between 5f and 6d than between 4f and 5d orbitals
(4)More reactive nature of the actinoids than the lanthanoids

Ans.(2) Being lesser energy difference between 5f and 6d than 4f and 5d orbitals.

33.In which of the following octahedral complexes of Co (at. no. 27), will be magnitude of A0 be the highest ?  (2008)
1) [Co(CN)6]3“              2) [Co(C204)3]3–
3) [Co(H20)6]3+             4) [Co(NH3)6]3+

Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-33

34.Knowing that the chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements in incorrect?(2009)
(1)Because of the large size of the Ln(III) ions the bonding in its compounds is predominantly ionic in character
(2)The ionic sizes of Ln(III) decreases in general with increasing atomic number
(3)Ln(III) compounds are generally colourless
(4)Ln(III) hydroxides are mainly basic in character

Ans.(3) Ln+3 compounds are mostly coloured.

35.Which of the following has an optical isomer?(2009)
1) [C0(NH3)3C1]\           2) [CO(en) (NH3)2]2+
3) [C0(H20)4(en)]3+        4) [CO(en)2(NH3)2]3+

Ans.(4) It is an octahedral complex of the type [M(AA)2X2] where AA is bidentate ligand.

36.In context with the transition elements, which of the following statements is incorrect ?(2009)
(1)In addition to the normal oxidation states, the zero oxidation state is also shown by these elements in complexes
(2)In the highest oxidation states, the transition metal show basic character and form cationic complexes.
(3)In the highest oxidation states of the first five transition elements (Sc to Mn), all the 4s and 3d electrons are used for bonding.
(4)Once the d3 configuration is exceeded, the tendency to involve all the 3d electrons in bonding decreases.
Ans.(2) In higher oxidation states transition elements show acidic nature.

37.Which of the following pairs represents linkage isomers ?   (2009)
(1)[Cu (NHj )4 ][PtCl4 ] and [Pt(NH,)4][CuCl4]
(2)[Pd (PPh3 )2 (NCS)2 ] and[Pd(PPh3)2(SCN)2]
(3)[CO(NH3)5N03]S04and [co(NH3)5S04]N03
(4)[PtCl2(NH3)4]Br2 and [PtBr2 (NH3)4]C12
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-37

38.A solution containing 2.675 g of CoCl3. 6NH3 (molar mass = 267.5g mol’1) is passed through a cation exchanger. The chloride ions obtained in solution were treated with excess of AgN03 to give 4.78g of AgCl (molar mass = 143.5 g mol-1). The formula of the complex is (At. Mass of Ag = 108u)                   (2010)
1)   [Co(NH3)6]C13         2)   [CoC12(NH3)JC1
‘ 3)    [CoC13(NH3)3]        4)    [CoC1(NH3)5]C12
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-38

39.Which one of the following has an optical isomer? (en = ethylenediamine)           (2010)
(1)[Zn(en) (NH3)2]2+   2)   [Co(en)3]3+
3)[Co(H20)4(en)]3+           4)         [Zn(en)2]2+
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-39
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-39-1
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-39-2

40.The magnetic moment (spin only) of [NiClJ2]-is     (2011)
1) 2.82 BM           2) 1.41 BM
(3)82 BM             4) 5.46 BM
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-40

41.Which of the following facts about the complex [Cr(NH3)6]Cl3 is wrong ?    (2011)
(1)The complex is an outer orbital complex
(2)The complex gives white precipitate with silver nitrate solution.
(3)The complex involves d2sp3 hybridisation and is octahedral in shape
(4)The complex is paramagnetic
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-41

42.In context of the lanthanoids, which of the following statements is not correct ? (2011)
(1)Because of similar properties the separation of lanthanoids is not easy
(2)Availability of 4f electrons results in the formation of compounds in + 4 state for all the members of the series
(3)There is a gradual decrease in the radii of the members with increasing atomic number in the series
(4)All the members exhibit + 3 oxidation state
Ans.(2) All the Lanthanides can not form + 4  oxidation state.

43.Which among the following will be named as dibromidohis (ethylenediamine) chromium (m) bromide ?    (2012)
1) [Cr(en)3]Br33             2) [Cr(en)2Br2]Br
3) [Cr(en)BrJ-                4) [Cr(en)Br2]Br
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-43

44.Which of the following complex species is not expected to exhibit optical isomerism ? (2013)
1) [Co(en)3]3+                 2) [Co(en)2C/2]+
3) [Co(NH3)C/3]       4) [Co(en)(NH3)2C/2]+
Ans.(3) [Co(NH3)3C/3] do not exhibit optical isomers but othee exhibit.

45.Which of the following arrangements does not represent the correct order of the property stated against it ?  (2013)
(1)V2+< CF+ < Mn2+ < Fe2+ :Paramagnetic behaviour
(2)Ni2+ < Co2+ < Fe2+ < Mn2+ : Ionic size
(3)Co3+ < Fe3+ < Cr3+ < Sc3+ :Stability in aqueous solution
(4)Sc < Ti < Cr < Mn :Number of oxidation states
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-45

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-46
Ans.(3) Order of wavelength of colours Red > Yellow > Green > Blue

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-48
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-47

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-49
Ans.(2)Two bidentate and two monodentative – ligands are present.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-48

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-50
Ans.(3) Change transfer from oxygen to manganese

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-d-blockf-block-and-complexes-51
Ans. (1) Ferrocyanide is blue.

JEE Main Home Maths Physics Chemistry

JEE Main Previous Year Papers Questions With Solutions Chemistry Elements of p-Block: Groups 13,14,15,16,17 and 18

JEE Main Previous Year Papers Questions With Solutions Chemistry  Elements of  p-Block: Groups 13,14,15,16,17 and 18

1.When H2S is passed through Hg2S we get(2002)
(1)HgS        2) HgS + Hg2S
3) Hg2S          4) Hg2S2
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-1

2.Alum helps in purifying water by (2002)
(1)forming Si complex with clay particles
(2)sulphate part which combines with the dirt and removes it
(3)coagulating the mud particles
(4)making mud water soluble
Ans.(3) Alum fumisheds Al3+ ions which bring about coagulation of negatively charged clay poarticles bacteria etc.

3.In case of nitrogen, NC13 is possible but not NC1S while in case of phosphorous, PC13 as well as PC15 are possible. It is due to (2002)
(1)availability of vacant d orbitals in P but not inN
(2)lower electronegativity of P than N
(3)lower tendency of H-bond formation in P than N
(4)occurrence of P in solid while N in gaseous state at room temperature
Ans.(1) 7N2 =ls22s23p3, 15P = 1 s22s22p63s23p3 In phosphorous the 3d – orbitals are available

4.Number of sigma bonds in P4O10 is (2003)
(1)6  2) 1            3) 17            4) 16 Ans.
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-4

5.What’happens when phosphine gas is mixed with chlorine gas ?    (2003)
(1)PC13 an HC1 are formed and the mixture warms up
(2)PC15 and HC1 are formed and the mixture cools down
(3)PH3.C12 is formed with warming up
(4)The mixture only cools down
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-5

6.Graphite is a soft solid lubricant extremely difficult to melt. The reasong for this anomalous behavior is that graphite. (2003)
(1)is an alio tropic form of diamond
(2)has molecules of variable molecular masses like polymers
(3)has carbon atoms arranged in large plates of rings of strongly bound carbon atoms with weak interplate bonds.
(4)is a non-crystalline substance.
Ans.(1) 4HC/ + 02–> 2Cl2 + 2H20  cloud of white fumes.

7.Concentrated hydrochloric acid when kept in open air sometimes produces a cloud of white fumes. The explanation for it is that (2003)
(1)oxygen in air reacts with the emitted HC1 gas to form a cloud of chlorine gas
(2)Strong affinity of HC1 gas for moisture in air results in forming of droplets of liquid solution which appears like a cloudy smoke.
(3)due to strong affinity for water. Concentrated hydrochloric acid pulls moisture of air towards itself. This moisture forms droplets of water and hence the cloud.
(4)concentrated hydrochloric acid emits strongly smelling HC1 gas all the time.
Ans.(3) Layers are held together.

8.Glass is a (2003)
(1)super -cooled liquid 2) gel
(3)polymeric mixture
(4)micro-crystalline solid
Ans.(1) Glass is a transparent or translucent super cooled liquid.

9.For making good quality mirrors plates of float glass are used. These are obtained by floating molten glass over a liquid metal which does not solidify before glass. The metal used can be    (2003)
(1)tin           2) sodium
3) magnesium               4) mercury
Ans.(4) It is because mercury exists as liquid at room temperature.

10.Which among the following factors is the mostimportant in making fluorine the strongest oxidizing halogen?(2004)
(1)Electron affinity
(2)Bond dissociation energy
(3)Hydration enthalpy 4) Ionization enthalpy
Ans.(2) Lower dissociation energy of bonds in F2.

11.Which one the following statement regarding helium is incorrect ?   (2004)
(1) It is used to fill gas balloons instead of H2because it is lighter and non-inflammable
(2)It is used in gas-cooled nuclear reactors
(3)It is used to produce and sustain powerful superconducting reagents (4)It is used as cryogenic agent for carrying out experiments at low temperatures
Ans.(1) Hydrogen is lightest and is non inflamable.

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-12

Ans.(4) Hydrated and coordinated aluminium cation is farmed

13.The soldiers of Napolean army while at Alps during freezing winter suffered a serious problem as regards to the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transforma­tion is related to(2004)
(1)an interaction with nitrogen of the air at very low temperatures
(2)an interaction with water vapour contained in the humid air
(3)a change in the partial pressure of oxygen in the air
(4)a change in the crystalline structure of tin
Ans.(4) Transformation of crystal structure.

14.The number of hydrogen atom(s) attached to phosphorus atom in hypophosphorous acid is
(2005)
(1)zero 2) two 3) one 4) three
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-14

15.The correct order of the thermal stability ofhydrogen halides (H – X) is                  (2005)
(1)HI > HBr > HC1 > HF
(2)HF > HC1 > HBr > HI
(3)HC1 < HF > HBr < HI
(4)HI > HC1 < HF < HBr
Ans.(2) HF is most stable.

16.Heating an aqueous solution of aluminiumchloride to dryness will give                (2005)
(1)A1C13 2) A12C16
3) A1203    4) Al(OH)CI2
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-16

17.In silicon dioxide (2005)
(1)Each silicon atom is surrounded by four oxygen atoms and each oxygen atom is bonded to two silicon atoms
(2)Each silicon atom is surrounded by two oxygen atoms and each oxygen atom is bonded to two silicon atoms
(3)Silicon atoms is bonded to two oxygen atoms
(4)There are double bonds between silicon and oxygen atoms
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-17

18.The structure of diborane (B2Hfi) contains(2005)
(1)four 2c-2e bonds and two 3c-2e bonds
(2)two 2c-2e bonds and four 3c-2e bonds
(3)two 2c-2e bonds and two 3c-3e bonds
(4)four 2c-2e bonds and four 3c-2e bonds
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-18

19.Which of the following chemical reactions depicts the oxidizing behaviour of H2S04 ?
(1)2HI + H2S04 -> I2 + S02 + 2H20 (2006)
(2)Ca(OH)2 + H2S04 CaS04 + 2H20
(3)NaCl + H2S04 NaHS04 + HC1
(4)2PC1S + H2S04 2POCl3 + 2HC1 + S02C12
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-19

20.A metal, M forms chlorides in its +2 and 44 oxidation states. Which of the following statements about these chlorides is correct ?
(1)MC12 is more volatile than MC14 (2006)
(2)MC12 is more soluble in anhydrous ethanol than MC14
(3)MC12 is more ionic than MC14
(4)MC12 is more easily hydrolysed than MC14
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-20

21.Which of the following statements is true ?
(1)H3PO3 is a stronger acid than H2S03 (2006)
(2)In aqueous medium HF is a stronger acid than HC1
(3)HC104 is a weaker acid than HC103
(4)HNO3 is a stronger acid than HN02
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-21

22.What products are expected from the disproportionation reaction of hypochlorous acid ?     (2006)
(1)HCIO3 and C120 2) HC102 and HC104
3) HC1 and C120           4) HC1 and HC103
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-22

23.The decreasing values of bond angles from NH3 (106°) to SbH3 (101°) down group-15 of the periodic table is due to        (2006)
(!)increasing bp-bp repulsion
(2)increasing p-orbital character in sp3
(3)decreasing lp-bp repulsion
(4)decreasing electronegativity
Ans.(4) Repulsions will be less with lower electronagativity.

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-24
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-24

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-25
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-25

26.Identify the incorrect statement among the fol­lowing (2007)
(1)Ozone reacts with S02 to give S03
(2)Silicon reacts with aqueous NaOH in the presence of air to give NajS^ and H20
(3)Cl2 reacts with excess of NH3 to give N2 and HC1
(4)Br2 reacts with hot and strong NaOH solu­tion to give NaBr, NaBr04 and H20
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-26

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-27
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-27

28.Which one of the following is the correct statement ?          (2008)
(1)Boric acid is a protonic acid
(2)Beryllium exhibits coordination number of six.
(3)Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase
(4)B2H6.2NH3 is known as ‘inorganic benzene’.
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-28

29.In which of the following arrangements, the e sequence is not strictly according to the property written against it ?      (2009)
(1)C02 < Si02 < Sn02 < Pb02 : increasing oxidising power
(2)HF < HC1 < HBr < HI : increasing acid strength
(3)NH3 < PH3 AsH3 < SbHj : increasing basic strength
(4)B<C<0<N: increasing first ionization enthalpy
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-29

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-30
Ans.(1) Xe03 is more stable than XeF6. All the remaining reactions are feasible

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-31
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-31

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-32
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-32

33.Which of the following statements regarding sulphur is incorrect ?                           (2011)
(1)At 600°C the gas mainly consists of S2 molecules
(2)The oxidation state of sulphur is never less than + 4 in its compounds
(3)S, molecule is paramagnetic
(4)The vapour at 200°C consists mostly of S8 rings
Ans.(2) Sulphur can exhibit – 2, + 2, + 1 oxidation states also.

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-34
Ans.(3) Stability of VA group hybrides decreases from NH3 to BiH3 due to the decrease in M – H bond energy.
NH3 > PH3 > AsH3 > SbH3 > BiH3
35.Which of the following on thermal decomposition yields a basic as well as an acidic oxide ?          (2012)
1) NaN03                      2) KC103
3) CaC03                       4) NH4N03
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-35

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-p-block-groups-1314151617-and-18-36
Ans.(1) ONF and ONO– are isoelectronic ON Cl and ONS– are isoelectronic

37.Which one of the following properties is not shown by NO ?                                     (2014)
(1)It’s bond order is 2.5 .
(2)It is diamagnetic in gaseous state
(3)It is a neutral oxide
(4)It combines with oxygen to form nitrogen dioxide
Ans.(2) NO is paramagnetic.

38.Among the following oxoacids, the correct decreasing order of acid strength is (2014)
(1)HC102 > HC104 > HCIO, > HOC1
(2)HCIO > HC102 > HCIO3 > HOCl4
(3)HC104 > HCIO > HC102 > HOCl3
(4)HC102 > HCIO3 > HC102 > HOC1
Ans.(4) With an increase in unprotonated oxygen atoms, acidic strength increases.

39.In the context of the Hall-Heroult process for the extration of Al, which of the following statements is false? (2015)
(1)CO and C02 are produced in this process
(2)A/203 is mixed with CaF2 which lowers the melting point of the mixture and brings conductivity
(3)A/3+ is reduced at the cathode to form Al
(4)Na3A/F6 is serves as the electrolyte
Ans.[4] A/203 is dissolved in cryolite which serves as electrolyte in molten state.

40.Which among the following is the most reactive ?               (2015)
1) C/2      2) Br2    3) I2 4) ICI
Ans.[4] Interhalogen compounds are polar and are more reactive.

41.Which one has the highest boiling point ?(2015)
(1) He 2) Ne 3) Kr (4) Xe
Ans.[4] Boiling point increases with an increase in Molecular mass.


JEE Main Home Maths Physics Chemistry

JEE Main Previous Year Papers Questions With Solutions Chemistry Elements of S-Block : Hydrogen,Group 1 and 2

JEE Main Previous Year Papers Questions With Solutions Chemistry  Elements of S-Block : Hydrogen,Group 1 and 2

1.K02(potassium super oxide) is used in oxygen cylinders in space and submarines. This is because it        (2002)
(1)absorbs C02 and increases 02 content
(2)eliminates moisture
(3)absorbs C02 4) produces ozone
Ans.(2) 2KO, + 2H20 —>2KOH + H202 + 02. Eliminates moisture.

2.A metal M readily forms its sulphate MS04which is water soluble. It forms its oxide MO which becomes inert on heating. It forms an insoluble hydroxide M(OH)2 which is soluble in NaOH solution. Then M is     (2002)
(1)Mg 2) Ba 3) Ca 4) Be
Ans.(4) Beryllium shows anomalous properties with alkaline earth metals, due to its small size.

3.In curing cement plasters water is sprinkled from time to time. This helps in           (2003)
(1)developing interlocking needle-like crystals of hydrated silicates.
(2)hydrating sand and gravel mixed with cement
(3)converting sand into silicic acid
(4)keeping it cool
Ans.(1) Cross links are developed during hydration of calcium aluminosilicates.

4.The substance not likely to contain CaC03 is
(1)calcined gypsum 2) sea shells (2003) 3) dolomite 4) a marble statue
Ans.(1) The composition of gypsum is CaS04. 2H20, while others are carbonates.

5.The solubilities of carbonates decrease down the magnesium group. This is due to a decrease in
(1)hydration energies of cations (2003)
(2)inter – ionic attraction
(3)entropy of solution formation
(4)lattice energies of solids
Ans.(1) The solubility is governed by AH soIution
AH solution– AHlattjce_ AHHydration.
Due to increase in size, the magnitude of hydration energy decreases and hence the solubility.

6.Several blocks of magnesium are fixed to the bottom of a ship to          (2003)
(1)make the ship lighter
(2)prevent action of water and salt
(3)prevent puncturing by under-sea rocks
(4)keep away the sharks
Ans.(2) Magnesium provides cathodic protection and prevent rusting or corrosion.

7.Which one of the following processes willproduce hard water ?      (2003)
(1)Saturation of water with MgCOa
(2)Saturation of water with CaS04
(3)Addition of Na2S04 to water
(4)Saturation of water with CaC03
Ans.(2) Permanent hardness of water is due to chlorides and sulphates of calcium and magnesium.

8.In hydrogen – oxygen fuel cell, combustion of hydrogen occurs to      (2004)
(1)generate heat
(2)remove adsorbed oxygen from electrode surfaces
(3)produce high purity water
(4)create potential difference between the two electrodes Ans.(4) Heat is converted directlyto electricity.
Ans.(4) Heat is converted directlyto electricity.

9.One mole of magnesium nitride on the reaction with an excess of water gives (2004)
(1)one mole of ammonia
(2)two moles of nitric acid
(3)two moles of ammonia
(4)one mole of nitric acid
Ans.(3) Mg3N2 +6H20——– » 3Mg(OH)2 + 2NH3

10.Hydrogen bomb is based on the principle of
(1)Nuclear fission (2005)
(2) Natural radioactivity
(3) Nuclear fusion
(4)Artificial radioactivity
Ans.(3) Fusion of isotopes of hydrogen.

11.Based on lattice energy and other considerations which one of the following alkali metal chlorides is expected to have the highest melting point.(2005)
1) LiCl       2) NaCl       3) KC1       4) RbCl
Ans.(2) Although lattice energy of LiCl higher than NaCl, but LiCl is covalent in nature and NaCl ionic. There after, the melting point decreases as we move NaCl because the lattice energy decreases as size of alkali metal atom increases. Higher lattice energy denotes higher melting and boiling points.

12.The ionic mobility of alkali metal ions in aqueous solution is maximum for (2006)
1) K+   2) Rb+  3) Li+   4) Na+
Ans.(2) Hydrated Rb+ has small size.

13.In context with the industrial preparation of hydrogen from water gas (CO+H2), Which of  the following is the correct statement ? (2008)
(1)CO and H2 are fractionally separated using differences in their densities
(2)CO is removed by absorption in aqueous Cu2Cl2 solution
(3)H2 is removed through occulsion with Pd
(4)CO is oxidised to C02 with steam in the presence of a catalyst followed by absorption of C02 in alkali
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-s-block-hydrogengroup-1-and-2-13

14. Very pure hydrogen (99.9%) can be made by ’ which of the following processes ?   (2012)
(1)Reaction of methane with steam
(2)Mixing natural hydrocarbons of high molecular weight
(3) Elecrolysis of water
(4)Reaction of salt like hydrides with water
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-s-block-hydrogengroup-1-and-2-14

15.The first ionization potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+ will be (2013)
1) -2.55 eV                   2) -5.1 eV
3)-10.2 eV                    4) +2.55 eV
Ans.(2) Inisation potential of alkali metal atom and electron affinity of its monocovalent cation are same in magnitude, but with opposite signs.

16.The metal that cannot be obtained by electrolysis of an aqueous solution of its salt is       (2014)
1) Cr 2) Ag 3) Ca 4) Cu
Ans.(3) Ca canot be obtained by the electrolysis of aqueous solution of its salt.

17.In which of the following reactions H202 acts as reducing agent ?     (2014)
a.H202 + 2H+ + 2e- -> 2H20
b.H202 – 2e–> 02 + 2H+
c.H202 + 2e- -> 20H-
d.H202 + 20H- 2e- -> 02 + 2H20
1) (b), (d)    2) (a), (b)      3) (c), (d)    4) (a), (c)
Ans.(1) While acting as reducing agent it gives up electrons and release oxygen gas.

jee-main-previous-year-papers-questions-with-solutions-chemistry-elements-of-s-block-hydrogengroup-1-and-2-18
Ans. 4) 2 mol of water softener require one mole of Ca2+

19.Form the following statements regarding H202, choose the incorrect statement (2015)
(1)It can act only as an oxidizing agent
(2)It decompose on exposure to light
(3)It has to be stored in plastic or was lined glass bottles in dark
(4)It has to be kept away form dust
Ans.(1) It is disproportionating agent.

20.Which one of the following alkaline earthmetal sulphates has its hydration enthalpy greater than its lattice enthalpy ?        (2015)
1) CaS04 2) BeS04 3) BaS04 4) SrS04
Ans.(2) Among alkaline earth metal sulphates BeS04 and MgS04 are water soluble due to high hydration enthalpy of Be2+ and Mg2+.


NCERT Solutions Home Page English Hindi Maths Science SocialRD Sharma

JEE Main Previous Year Papers Questions With Solutions Chemistry Basic Concepts and Stoichiometry

JEE Main Previous Year Papers Questions With Solutions Chemistry Basic Concepts and Stoichiometry

Multlple Choice with ONE correct answer
1.In the formula X = 3YZ2, X and Z have dimensions of capacitance and magnetic induction respectively. What are the dimensions of Y in MKSQ system ?     [1995-2 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-1
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-14

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and stoichiometry-2
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-15

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-3
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-16

4.A cube has a side of length 2 x 10-2m. Calculate its volume.     [2003-2 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-4
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-17

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-5
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-18
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-19

6.A wire of length 1 = 6±0.06 cm and radius r = 0.5 ± 0.005 cm and mass m = 0.3 ± 0.003 g . Maximum percentage error in density is [2004-2 marks]
a) 4      b) 2           c) 1                d) 6.8
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-20
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-21

7.Which of the following sets have different dimensions ? [2005-2 marks]
a)Pressure, Young’s modulus, stress
b)Emf, potential difference, electric potential
c)Heat, work done, energy
d)Dipole moment, electric flux, electric field
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-22

8.The density of a solid ball is to be determined in an experiment. The diameter of the ball is measured with a screw gauge, whose pitch is 0.5 mm and there are 50 divisions on the circular scale. The reading on the main scale is 2.5 mm and that on the circular scale is 20 divisions. If the measured mass of the ball has a relative error of 2%, the relative percentange error in the density is
a) 0.9%     b) 2.4% c) 3.1%  d) 4.2%
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-23

Multiple Choice with ONE or  More Than ONE correct answers
9.If L,C,R represent inductance, capacitance and resistance respectively, the combinations having dimensions of frequency are [1984-2 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-6
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-24

10.Which of the following combinations have the dimensions of time ? L,C,R represent inductance, capacitance and resistance respectively [1986-2 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-7
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-25

11.The dimensions of the quantities in one (or more) of the following pairs are the same. Identify the pair(s)  [1986-2 marks]
a) Torque and work                              b) Angular momentum and work
c) Energy and Young’s modulus        d) Light year and wavelength
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-26

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-8
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-27

13.The pairs of physical quantities that have the same dimensions in (are)     [1995-2 marks]
a)Reynolds number and coefficient of friction
b)Curie and frequency of a light wave
c)Latent heat and gravitational potential
d)Planck’s constant and torque
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-28

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-9
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-29

15.The ST unit of inductance, the henry can be written as   [1998-2 marks]
a)weber/ampere          b)     volt-sec/amp
c) joule/(ampere)2        d) ohm-second
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-30

Matching Type
16.Match the physical quantities given in Column 1 with dimensions expressed in terms of mass (M), length (L), time (T), and charge (Q) given in Column II
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-10
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-31

17.Column-I gives three physical quantities. Select the appropriate units for the choices given in Column-II. Some of the physical quantities may have more than one choice correct [1990-3 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-11
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-32

18.Some physical quantities are given in column I and some possible SI units in which these quantities may be expressed are given in Coulmn II. Match the physical quantities in column I with the units in Column II……………………..  [2007-6 marks]
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-12
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-33
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-34

Subjective / Numerical integer type
19.Give the MKS units for each of the following quantities :   [1980-3 marks]
i) Young’s modulus  ii) Magnetic induction  iii) Power of a lens
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-35

20.A gas bubble, from an explosion under water,oscillates with a period T proportional to padbEc • Where P is the static pressure, d is the density of water and E is the total energy of the explosion. Find the   values of a,b and c            [1981-3 marks]
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-36

21.Write the dimensions of the following in terms of mass, time, length and charge
i) magnetic flux ii) rigidity modulus [1982-2 marks]
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-37

Fill in the blanks
22.Planck’s constant has dimensions………………. [1985-2 marks]
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-38

23.In the formula X = 3YZ2,X and Z have dimensions of capacitance and magnetic induction respectively. The dimensions of Y in MKSQ system are………………………[1988-2 marks]
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-39

24.The dimensions of electrical conductivity is…………………..  [1997-1 mark]
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-40

jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-13
Ans.
jee-main-previous-year-papers-questions-with-solutions-chemistry-basic-concepts-and-stoichiometry-41

JEE Main Home Maths Physics Chemistry