52671 + Interview Questions in Chemistry in Class 11

1.	Metals like Pt and Pd can adsorb large volume of hydrogen under specific conditions. Such adsorbed hydrogen by the metal is known as
Answer» OCCLUDED hydrogen Absorbed hydrogen Reactive hydrogen Atomic hydrogen Answer :A

Discussion

2.	Metals having ns' as the valence electronic configuration
Answer» act as STRONG oxidising agents are HIGHLY electronegative are highly electropositive have a FIRST IONIZATION potential of more than Answer :C

Discussion

3.	Metals have high thermal conductivity. Give reason.
Answer» Solution :High themal CONDUCTIVITY of METALS is due to thermal excitation of many ELECTRONS from the valence band to the CONDUCTION band.

Discussion

4.	Metals have _________ density .
Answer» SOLUTION :The ELECTROSTATIC attraction between the metal ions and the free electrons yields a three DIMENSIONAL close packed crystal with a large number of NEAREST metal ions. So metals have HIGH density.

Discussion

5.	Metal(s) generally obtained by the reduction of their oxides with H_(2) are
Answer» Al, Zn MO, W Na, K Ca, Mg. Solution :Molybdenum (Mo) and trugesten (W) are OBTAINED by the reduction of their OXIDES with hydrogen.

Discussion

6.	Metals form basic hydroxides. Which of the following metal hydroxides is the least basic?
Answer» `MG(OH)_(2)` `CA(OH)_(2)` `Sr(OH)_(2)` `Ba(OH)_(2)` SOLUTION :BASIC character of the hydroxide increases down the GROUP as the size of metal increases. Solubility of hydroxide increases and hydroxide of Be and Mg are almost insoluble.

Discussion

7.	Metals form basic hydroxides . Which of the following metal hydroxide is the least basic ?
Answer» `Mg(OH)_(2)` `CA(OH)_(2)` `SR(OH)_(2)` `BA(OH)_(2)` Solution :As the ionization ENTHALPY increases from `Mg to Ba`, the M-O bond becomes weaker and weaker down the group and hence basicity increases down the group . Thus , `Mg(OH)_(2)` is least basic .

Discussion

8.	Metals commonly extracted by Gold Schmidt's alumino-thermic process is/are
Answer» GOLD Chromium Iron Maganese Solution :Gold and iron are not extracted by Goldschmidt's aluminothermic PROCESS. Gold never exists as oxide, iron if extracted by this METHOD will most many TIMES more than its cost in the market.

Discussion

9.	Thecrystals which are good conductors of electricity and heat are
Answer» Solution :(i) The bonding in METAL is explained by molecular ORBITAL theory. As per this theory, the atomic ORBITALS of large number of atoms in a crystal overlap to form numerous bonding and anti-bonding molecular orbitals without any band GAP. (ii) The bonding molecular orbitals are completely filled with an ELECTRON pair in each, and the anti-bonding molecular orbitals are empty. (iii) Absence of band gap accounts for high clectrical conductivity of metals.

Discussion

10.	Metals are ductile in nature. Why?
Answer» SOLUTION :In the close. packed structure of metallie erystal, it contains many slip planes along which MOVEMENT can occur during MECHANICAL loading, so the metal ACQUIRES ductility.

Discussion

11.	Metalloid elements are placed in
Answer» <P>S - BLOCK p - Block d - Block F - Block ANSWER :B

Discussion

12.	Metallic tin in the presence of HCl is oxidised by K_(2)Cr_(2)O_(7) solution to stannic chloride. What volume of decinormal dichromate solution would be reduced by 1 g of Sn ?
Answer» Solution :`underset(3xx118.7 g)(3SN)+underset(2xx294 g)(2K_(2)Cr_(2)O_(7))+28 HCl to 3SnCl_(4)+4KCl+4CrCl_(3)+14H_(2)O` `K_(2)Cr_(2)O_(7)` required for 1 g of Sn`=(2xx294)/(3xx118.7)=1.65 g`

Discussion

13.	Metallic magnesium has a hexagonal close packed structure and a density of 1.74 g//cm^3. Assuming magnesium atoms to be spherical, calculate the volume of eachatom and atomic radius of Mg atom (Atomic mass of Mg =24)
Answer» Solution :As MG has HEXAGONAL close packed structure , no. of atoms per unit cell = 6 , i.e., Z=6 `rho=(ZxxM)/(a^3xxN_0)=(ZxxM)/(VxxN_0)` (V=`a^3`=volume of the unit cell) `therefore 1.74 =(6xx24)/(Vxx(6.023xx10^23))` or `V=1.374xx10^(-22) cm^3` Now , as in hexagonal close packing , 74% of the space is occupied by atoms, therefore, volume occupied by atoms =`74/100xxV` `=74/100xx1.374xx10^(-22) =1.018xx10^(-22) cm^3` As a unit cell contains 6 Mg atoms, therefore , volume of each Mg atom `=(1.018xx10^(-22))/6=1.697xx10^(-23) cm^3` As Mg atom is ASSUMED to be spherical, `therefore 4/3pir^3 =1.697xx10^(-23)` On SOLVING, we GET `r=1.594xx10^(-8)` cm =1.594 Å

Discussion

14.	Metallic magnesium has a hexagonal close packed structure and a density of 1.74 g//cm^(3) . Assuming magnesium atoms to be spherical, calculatethe volume of each atom and atomic radium of Mg atoms (Atomic mass ofMg= 24)
Answer» <P> Solution :As MG has hexagonal close packed structure , no. of atoms per unit cell = 6 ,i.e,Z = 6 `p= (Z XX M)/( a^(3)xxN_(0)) = (Z xxM)/(V xx N_(0)) "" (V =a^(3)`= VOLUME of the unit cell) ` 1.74 = ( 6xx24)/( V xx (6.023 xx10^(23))) orV = 1.374 xx 10^(-22)cm^(3)` Now ,as in hexagonal close packing, 74%of the space is occupiedby atoms, therefore, volume occiped by atoms ` = 74/100 xx V` ` = 74/100 xx 1.734 xx 10^(-22) = 1.018 xx 10^(-22)cm^(3)` As a unit cell contains 6 Mg atom, therefore, volume of each Mg atom. `( 1.018 xx 10^(-22))/6= 1.697 xx 10^(-23) cm^(3)` As Mg is assumed to be spherical. ` 4/3 pir^(3) = 1.697 xx 10^(-23)` on solving we get ` r =1.594 xx 10^(-8)cm= 1.594Å`

Discussion

15.	Metallic magensium has a hexagoanl close-packed structure and a density of 1.74 g //cm^(3). Assume magnesium atoms to be sphere of radius r. 74.1 % of the space is occupied by atoms. Calculate the volume of each atom and the atomic radius r.(Mg = 24.31)
Answer» Answer :`1.72 XX 10^(-23) CM^(3), 1.60 Å`

Discussion

16.	Metallic lustre is explained by
Answer» Diffusion of metal ions Oscillation of looseelectrons Excitation of FREE protons Existence of BCC lattice Solution :Metallic lustre is explained by oscillation of LOOSE ELECTRONS.

Discussion

17.	Metallic Iusture is explained by
Answer» Diffusion of metal IONS Oscillations of loose electrons Excitation of FREE protons EXISTENCE of BCC LATTICE Solution :Oscillating free electrons explain the metallic lusture.

Discussion

18.	Metallic________ is usedfor makingwindowsofXraytubes .
Answer» MAGNESIUM beryllium sulphur Magnalium ANSWER :B

Discussion

19.	Metallic hydrides are otherwise called ................
Answer» SALT HYDRIDES Saline hydrides Covalent hydrides INTERSTITIAL hydrides Solution :Interstitial hydrides

Discussion

20.	Metallic hydride is formed by reaction of hydrogen with
Answer» Iron MANGANSE PALLADIUM Molybdenum Solution :Metallic HYDRIDE is formed by palladium.

Discussion

21.	Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties?
Answer» High boiling point High NEGATIVE standard electrode potential High density Large atomic SIZE Solution :Alkali metals have LARGEST size and low density and have low boiling point. These metals lose ELECTRONS easily DUE to less effective nuclear charge and have high negative standard electrode potential.

Discussion

22.	Metallic elements are described by their standard electrodepotential , fusion enthalpy , atomic size , etc . The alkali metals are characterised by which of the following properties ?
Answer» High boiling point High negative STANDARD ELECTRODE POTENTIAL High density LARGE atomic size SOLUTION :Alkali metals have high negative standard electrode potential and large atomic size .

Discussion

23.	Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties? (i) High boiling point (ii) High density (iii) Large atomic size
Answer» I & ii I & III only ii only iii Answer :D

Discussion

24.	Metallic calcium is prepared by.....
Answer» DISPLACEMENT of calcium by IRON from calcium SULPHATE SOLUTION. electrolysis of MOLTEN calcium chloride. reduction of lime by coke. electrolysis of aqueous solution of calcium nitrate. Answer :C

Discussion

25.	Metalic ti in resence of HCI is oxidised by K_(2)Cr_(2)O_(7) to stannic chloide whast volume of decinormal in aicdic medium?
Answer» Solution :BALANCED chemical equation is `2K_(2)Cr_(2)O_(7)+3Sn+28HCIrarr4KcI+4 CrCI_(3)+3 SnCI_(4)+14 H+_(2)O` `2(2xx39+2xx52+7xx16)=356.1 g` Now 356.1 Sn react with `K_(2)Cr_(2)O_(7)=(588)/(356.1)g=1.651 g` Eq .wt of `K_(2)CrO_(7)=("mol.wt")/(6)=(294)/(6)=49` Decinormak `K_(2)Cr_(2)O_(7)` slution means 1000 mL solution CONTAINS 4.9 g`K_(2)Cr_(2)O_(7)i.e 4.9 g K_(2)Cr_(2)O_(7)` are present in 1000 mL solution `therefore` 1.651 g willbe present in =`(1000)/(4.9)xx1.651=336.9 mL`

Discussion

26.	Metaldehyde is the product of the following
Answer» `4CH_(3)-CHOoverset(Conc.H_(2)SO_(4),0^(@)C)to` `CH_(3)-overset(O)overset(\|\|)C-CH_(3)overset(Conc.H_(2)SO_(4), ro omtemp.)to` `3CH_(3)CHOoverset(Conc.H_(2)SO_(4),ro omtemp.)to` `C_(6)H_(5)-CHO overset("conc.H_(2)SO_(4))to` ANSWER :3

Discussion

27.	Metallic radius of Ca is 200pm. Covalent radius of Ca is
Answer» 200 PM 230 pm 280 pm 174 pm Answer :D

Discussion

28.	Metal which obtained by reduction with carbon is
Answer» Fe Zn Pb Cu Answer :D

Discussion

29.	Metal which cannot be refined by electrolytic refining process is
Answer» Cu Cr Ni Al Answer :B

Discussion

30.	Metal which cannot be extracted by smelting process is
Answer» Pb Fe Zn Al. Answer :D

Discussion

31.	Metal used for dying organic solvents is
Answer» Fe Pt Mg Na. Solution :Because it REACTS with WATER and REMOVES it.

Discussion

32.	Metal that escapes into atmosphere by the fumes of automobile vehicles
Answer» Hg Pb Na Cu ANSWER :B

Discussion

33.	Metal used as catalyst in the hydrogenation of vegetable oils
Answer» Iron Molybdenum Nickel Sodium ANSWER :C

Discussion

34.	Metal protected by a layer of its own oxide is
Answer» AL Ag Au B Solution :Al is very REACTIVE towards oxygen GIVES an OXIDE LAYER `4 Al + 3O_(2)rarr2Al_(2)O_3`

Discussion

35.	Metal ions are activatorsand increase catlyticactivity of enzymemolecular. If water vapours is assumed to be a perfect gas, molar enthalpychangefor vaporisationof 1 mole of water1 bar 100^(@)C is 41 kJ//mol. Choose the correct statement(s).(TakenR= 8.3 J//"mole"//K)
Answer» `DeltaU_("VAPORISATION")`of1 MOLEOF WATER at 1 barand `100^(@)C= 37.904 kJ//"mol"` `(DeltaU=DeltaH)` forconversion of thewaterinto ice at `0^(@)C` In theisothermalprocessof (b), `DeltaH=0` `(DeltaH=DeltaU)` for conversion of 1 mole of water into steam`100^(@)`C Answer :a,b

Discussion

36.	Metal ion M^(+3) loses three electrons than what will be its oxidation number ?
Answer» SOLUTION :`M^(+3)TOM^(+6)+3E^(-)`

Discussion

37.	Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH , CsH, the correct order of increasing ionic character is
Answer» `LiH GT NaH gt CSH gt KH gt RbH` `LiH LT NaH lt KH lt RbH lt CsH` `RbH gt CsH gt NaH gt KH gt LiH` `NaH gt CsH gt RbH gt LiH gt KH` Solution :IONIC characterincreases as the size of the ATOM increases or the electronegativity of the atom decreases, i.e., `LiH lt NaOH lt KH lt RbH lt CsH`.

Discussion

38.	Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RBH, CSH, the correct order of increasing ionic character is ......
Answer» LiH > NaH > KH > RbH > CsH LiH < NaH < KH < RbH < CsH RbH < CsH < LiH < KH < NaH NaH > CsH > LiH > RbH > KH Solution :LiH < NAL

Discussion

39.	Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH and CsH, the correct order of increasing ionic character is
Answer» `LiH gt NaH gt CsH gt KH gt RBH` `LiH LT NaH lt KH lt RbH lt CsH` `RbH gt CsH gt NaH gt KH gt LiH` `NaH gt CsH gt RbH gt LiH gt KH` Solution :Ionic character INCREASE as the size of the atom increases or the ELECTRONEGATIVITY of the atom decreases : `LiH lt NaH lt KH lt RbHlt CsH`

Discussion

40.	Metal carbonates decompose on heating to give metal oxide and carbon dioxide . Which of the metal carbonates is most stable thermally ?
Answer» `MgCO_(3)` `CaCO_(3)` `SrCO_(3)` `BaCO_(3)` SOLUTION :Thermal stability of metal carbonates increases as the ELECTROPOSITIVE character of the metal or the BASICITY of the metal HYDROXIDE increases from `Be(OH)_(2)` to `Ba(OH)_(2)` . Thus `BaCO_(3)` is most stable .

Discussion

41.	Metal carbonates decompose on heating to give metal oxide and carbon dioxide. Which of the metal carbonates is most stable thermally?
Answer» `MgCO_(3)` `CaCO_(3)` `SiCO_(3)` `BaCO_(3)` Solution :Thermal stability of `MCO_(3)` Group-2 depends on the MO. If MO is stable `MCO_(3)`is thermally unstable and vice versa. `MCO_(3) to MO+CO_(2)`. Thermal stability of MO decreases as the size of M increases. Therefore, BaO is least stable and `BaCO_(3)`is most stable.

Discussion

42.	Metal carbonate on reaction with ........ acid gives nitrate.
Answer» NITROUS acid Nitric acid Picric acid Sulphuric acid Answer :B

Discussion

43.	Metal atom with atomic number 21 has the differentiating electron enetering in 3d but not in 4s. However, in the formation of divalent cation 4s electrons are removed. Why?
Answer» Solution :While filling ELECTRONS 4s is filled FIRST and then 3D, based on Auf-bau PRINCIPLE. During the FORMATION of divalent cation, it is easy to remove lectrosn from 4s compared to that of 3d.

Discussion

44.	Metal A when burnt in air forms only an oxide while metal B When brunt in air forms a mixture of oxide and nitride. A and B are
Answer» MG and Ca K and Mg Be and Ca Na and Ca Solution :K can FORM only OXIDES when reacts with air and Mg can form oxide and nitride.

Discussion

45.	Metal A reduces silica converting itself into B. B absorbs moisture an converts into C. When C is heated with the reduction product of silica liberates a gas. Then A,B,C and gas are
Answer» `Na, Na_(2)O, NAOH, H_(2)` `Na, Na_(2)O_(2), Na_(2)CO_(3), O` `Na, Na_(2)O, Na_(2)CO_(3), CO_(2)` `Na, Na_(2)O_(2), NaOH, H_(2)` SOLUTION :`SiO_(2)+NararrSi+Na_(2)Ooverset(H_(2)O)rarrNaOH`

Discussion

46.	Meta-directing and deactivating group in aromatic electrophilic substitution is
Answer» `-CH_(3)` `-OH` `-NO_(2)` `-CL` SOLUTION :`-CH_(3) ""` Activaing and o, p-directing `-OH ""` ACTIVATING and o, p-directing `-NO_(2) ""` DEACTIVATING and m-directing `-Cl ""` Deactivating and o, p-directing `-OCH_(3) ""` Activating and o, p-directing

Discussion

47.	Meta directing group in electrophilic substitution in benzene nucleus is
Answer» `-O-UNDERSET(O)underset(\|\|)C-CH_3` `-OVERSET(O)overset(\|\|)C-O-CH_3` `-NH-overset(O)overset(\|\|)C-CH_3` `-NH_2` SOLUTION :`-overset(O)overset(\|)C - O-CH_3`

Discussion

48.	Met-enkephalin, an endorphin, serves as natural pain reliver that changes or removes the perception of nerve signals, How many types of functional groups are present in Met-enkephalin.
Answer» ANSWER :6

Discussion

49.	Mesoxalic acid is obtained when glycerol reacts with
Answer» Dil. `HNO_(3)` `BI(NO_(3))_(2)` `H_(2)O_(2)+FeSO_(4)` `KMnO_(4)` SOLUTION :`{:(COOH),("\|"),(C=O),("\|"),(COOH):}` Mesoxalic acid

Discussion

50.	Mesomeric effect is a permanent effect in which pi electrons are transferred from a
Answer» Multiple bond to an atom Multiple bond to a single COVALENT bond Both 1 and 2 None Answer :C

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Metals like Pt and Pd can adsorb large volume of hydrogen under specific conditions. Such adsorbed hydrogen by the metal is known as

Metals having ns' as the valence electronic configuration

Metals have high thermal conductivity. Give reason.

Metals have _________ density .

Metal(s) generally obtained by the reduction of their oxides with H_(2) are

Metals form basic hydroxides. Which of the following metal hydroxides is the least basic?

Metals form basic hydroxides . Which of the following metal hydroxide is the least basic ?

Metals commonly extracted by Gold Schmidt's alumino-thermic process is/are

Thecrystals which are good conductors of electricity and heat are

Metals are ductile in nature. Why?

Metalloid elements are placed in

Metallic tin in the presence of HCl is oxidised by K_(2)Cr_(2)O_(7) solution to stannic chloride. What volume of decinormal dichromate solution would be reduced by 1 g of Sn ?

Metallic magnesium has a hexagonal close packed structure and a density of 1.74 g//cm^3. Assuming magnesium atoms to be spherical, calculate the volume of eachatom and atomic radius of Mg atom (Atomic mass of Mg =24)

Metallic magnesium has a hexagonal close packed structure and a density of 1.74 g//cm^(3) . Assuming magnesium atoms to be spherical, calculatethe volume of each atom and atomic radium of Mg atoms (Atomic mass ofMg= 24)

Metallic magensium has a hexagoanl close-packed structure and a density of 1.74 g //cm^(3). Assume magnesium atoms to be sphere of radius r. 74.1 % of the space is occupied by atoms. Calculate the volume of each atom and the atomic radius r.(Mg = 24.31)

Metallic lustre is explained by

Metallic Iusture is explained by

Metallic________ is usedfor makingwindowsofXraytubes .

Metallic hydrides are otherwise called ................

Metallic hydride is formed by reaction of hydrogen with

Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties?

Metallic elements are described by their standard electrodepotential , fusion enthalpy , atomic size , etc . The alkali metals are characterised by which of the following properties ?

Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties? (i) High boiling point (ii) High density (iii) Large atomic size

Metallic calcium is prepared by.....

Metalic ti in resence of HCI is oxidised by K_(2)Cr_(2)O_(7) to stannic chloide whast volume of decinormal in aicdic medium?

Metaldehyde is the product of the following

Metallic radius of Ca is 200pm. Covalent radius of Ca is

Metal which obtained by reduction with carbon is

Metal which cannot be refined by electrolytic refining process is

Metal which cannot be extracted by smelting process is

Metal used for dying organic solvents is

Metal that escapes into atmosphere by the fumes of automobile vehicles

Metal used as catalyst in the hydrogenation of vegetable oils

Metal protected by a layer of its own oxide is

Metal ions are activatorsand increase catlyticactivity of enzymemolecular. If water vapours is assumed to be a perfect gas, molar enthalpychangefor vaporisationof 1 mole of water1 bar 100^(@)C is 41 kJ//mol. Choose the correct statement(s).(TakenR= 8.3 J//"mole"//K)

Metal ion M^(+3) loses three electrons than what will be its oxidation number ?

Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH , CsH, the correct order of increasing ionic character is

Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RBH, CSH, the correct order of increasing ionic character is ......

Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH and CsH, the correct order of increasing ionic character is

Metal carbonates decompose on heating to give metal oxide and carbon dioxide . Which of the metal carbonates is most stable thermally ?

Metal carbonates decompose on heating to give metal oxide and carbon dioxide. Which of the metal carbonates is most stable thermally?

Metal carbonate on reaction with ........ acid gives nitrate.

Metal atom with atomic number 21 has the differentiating electron enetering in 3d but not in 4s. However, in the formation of divalent cation 4s electrons are removed. Why?

Metal A when burnt in air forms only an oxide while metal B When brunt in air forms a mixture of oxide and nitride. A and B are

Metal A reduces silica converting itself into B. B absorbs moisture an converts into C. When C is heated with the reduction product of silica liberates a gas. Then A,B,C and gas are

Meta-directing and deactivating group in aromatic electrophilic substitution is

Meta directing group in electrophilic substitution in benzene nucleus is

Met-enkephalin, an endorphin, serves as natural pain reliver that changes or removes the perception of nerve signals, How many types of functional groups are present in Met-enkephalin.

Mesoxalic acid is obtained when glycerol reacts with

Mesomeric effect is a permanent effect in which pi electrons are transferred from a