94420 + Interview Questions in Chemistry in Class 12

1.	Gasoline is obtained from crude petroleum oil by its
Answer» FRACTIONAL distillation Vacuum distillation Steam distillation Pyrolysis Solution :Fractional distillation is USED because the difference between the BOILING point of different COMPONENT is LESS

Discussion

2.	What is shape selective catalysis? Give an example of such type of catalyst.
Answer» SOLUTION :ZEOLITE or `ZSM - 5`.

Discussion

3.	Gasoline infact is a poor fuel for internal combustion engine. When such fuels are used in an engine, combustion can be inititatedbefore tha spark plug fires. This produces 'Knocking ' oror 'Pinging ' in the running engine. The quality of fuel is indicated by its octane number . Straight chain hydrocarbons have low octane number . A scale was set up to evaluate this important knock property of gasoline.Iso-octane ,an excellent fuel with a highly branchedstructure, was arbitrarrily given a rating ( octane number =100 ), n- Heptane being a poor fuel was given the octane number of zero. The octane number of gasoline can also be increased by the addition of other compoundsbesides the tetraethyl lead (TEL) which is a pollutant. The compond used in asoline to improve its quality or octane number are : BTX: Benzene Toluene Xylene TBA= Tertiary Butyl Alcohol MTBE: Methyl Tertiary Butyl Alcohol Quality of diesel fuel is measured in terms of cetane number . Cetane compound is already given 100 cetane number whereas alpha-methyl nepthalene is given the centane number zero . Answer the following question : Octanenumberforegular gasoline is 87.It has sameknoking propeartay as:
Answer» A mixture containing87% ISO -octane and13%heptane a MIXTURECONTAINING 13%iso - octane and 87% heptane 87 giso - octanedissolved in 1 litrealcohol 13 g iso -octane DISSOLVED in 1litre water ANSWER :A

Discussion

4.	Give an example of primary cell.
Answer» SOLUTION : Leclanche CELL

Discussion

5.	Gasoline infact is a poor fuel for internal combustion engine. When such fuels are used in an engine, combustion can be inititatedbefore tha spark plug fires. This produces 'Knocking ' oror 'Pinging ' in the running engine. The quality of fuel is indicated by its octane number . Straight chain hydrocarbons have low octane number . A scale was set up to evaluate this important knock property of gasoline.Iso-octane ,an excellent fuel with a highly branchedstructure, was arbitrarrily given a rating ( octane number =100 ), n- Heptane being a poor fuel was given the octane number of zero. The octane number of gasoline can also be increased by the addition of other compoundsbesides the tetraethyl lead (TEL) which is a pollutant. The compond used in asoline to improve its quality or octane number are : BTX: Benzene Toluene Xylene TBA= Tertiary Butyl Alcohol MTBE: Methyl Tertiary Butyl Alcohol Quality of diesel fuel is measured in terms of cetane number . Cetane compound is already given 100 cetane number whereas alpha-methyl nepthalene is given the centane number zero . Answer the following question : selectthe correct statementanoutthe efficiencyof gasoline:
Answer» branched alklanes arebetter fuelthanstright chain alkane lesser is theoctane NUMBERGREATER is theefficiency of FUEL HIGHQUALITY fuel has greater klnoking property All of THEABOVE Answer :A

Discussion

6.	Give an example of network polymer.
Answer» SOLUTION :BAKELITE

Discussion

7.	Gasoline infact is a poor fuel for internal combustion engine. When such fuels are used in an engine, combustion can be inititatedbefore tha spark plug fires. This produces 'Knocking ' oror 'Pinging ' in the running engine. The quality of fuel is indicated by its octane number . Straight chain hydrocarbons have low octane number . A scale was set up to evaluate this important knock property of gasoline.Iso-octane ,an excellent fuel with a highly branchedstructure, was arbitrarrily given a rating ( octane number =100 ), n- Heptane being a poor fuel was given the octane number of zero. The octane number of gasoline can also be increased by the addition of other compoundsbesides the tetraethyl lead (TEL) which is a pollutant. The compond used in asoline to improve its quality or octane number are : BTX: Benzene Toluene Xylene TBA= Tertiary Butyl Alcohol MTBE: Methyl Tertiary Butyl Alcohol Quality of diesel fuel is measured in terms of cetane number . Cetane compound is already given 100 cetane number whereas alpha-methyl nepthalene is given the centane number zero . Answer the following question : selectthecorrectstatements amongthe following:
Answer» Cetane NUMBER is ASSIGNED fordiesal Fuel cetanenumberis assigned for KEROSENE oil greater is the centane numbermore efficientis thefuel centanenumberandoctane number are same . Answer :A,C

Discussion

8.	Give an example of narcotic which is used as an analgesic.
Answer» SOLUTION :MORPHINE.

Discussion

9.	Gasoline infact is a poor fuel for internal combustion engine. When such fuels are used in an engine, combustion can be inititatedbefore tha spark plug fires. This produces 'Knocking ' oror 'Pinging ' in the running engine. The quality of fuel is indicated by its octane number . Straight chain hydrocarbons have low octane number . A scale was set up to evaluate this important knock property of gasoline.Iso-octane ,an excellent fuel with a highly branchedstructure, was arbitrarrily given a rating ( octane number =100 ), n- Heptane being a poor fuel was given the octane number of zero. The octane number of gasoline can also be increased by the addition of other compoundsbesides the tetraethyl lead (TEL) which is a pollutant. The compond used in asoline to improve its quality or octane number are : BTX: Benzene Toluene Xylene TBA= Tertiary Butyl Alcohol MTBE: Methyl Tertiary Butyl Alcohol Quality of diesel fuel is measured in terms of cetane number . Cetane compound is already given 100 cetane number whereas alpha-methyl nepthalene is given the centane number zero . Answer the following question : Hexadecane is commonly called :
Answer» OCTANE centane GASOHOL NATALITE ANSWER :B

Discussion

10.	Gasoline infact is a poor fuel for internal combustion engine. When such fuels are used in an engine, combustion can be inititatedbefore tha spark plug fires. This produces 'Knocking ' oror 'Pinging ' in the running engine. The quality of fuel is indicated by its octane number . Straight chain hydrocarbons have low octane number . A scale was set up to evaluate this important knock property of gasoline.Iso-octane ,an excellent fuel with a highly branchedstructure, was arbitrarrily given a rating ( octane number =100 ), n- Heptane being a poor fuel was given the octane number of zero. The octane number of gasoline can also be increased by the addition of other compoundsbesides the tetraethyl lead (TEL) which is a pollutant. The compond used in asoline to improve its quality or octane number are : BTX: Benzene Toluene Xylene TBA= Tertiary Butyl Alcohol MTBE: Methyl Tertiary Butyl Alcohol Quality of diesel fuel is measured in terms of cetane number . Cetane compound is already given 100 cetane number whereas alpha-methyl nepthalene is given the centane number zero . Answer the following question : what is theIUPAC nameof thecompound havingoctanenumberequalto 100?
Answer» N- Heptane 2,2,4-Trimethylpentane ,2,2,3 -Trimethylhaptae 2,2,4,4-Tertramethylbutane ANSWER :B

Discussion

11.	Give an example of linkage isomerism.
Answer» Solution :`[Co(NO_(2))(NH_(3))_(5)]Cl_(2)` and `[Co(ONO)(NH_(3))_(5)]Cl_(2)`.

Discussion

12.	Gasoline has compoundshaving composition
Answer» `C_3-C_5` `C_8-C_(12)` `C_6-C_(10)` `C_(10)-C_(13)` ANSWER :C

Discussion

13.	Give an example of linkage isomerism
Answer» Solution :`[Co(NH_(3))_(5)NO_(2)]Cl` and `[Co(NH_(3))_(5)(ONO)]Cl_(2)`

Discussion

14.	Gasoline has composition
Answer» `C_8 -C_12` `C_2-C_5` `C_6-C_8` None of these Solution :The approximate composition of GASOLINE is `C_6 - C_8` at BOILING point `70-120^@C` and is USED in MOTOR fuel, DRY cleaning , petrol gas etc.

Discussion

15.	Give an example of ionization isomerism
Answer» SOLUTION :`[Co(NH_(3))_(5)Cl]SO_(4) and [Co(NH_(3))_(5)SO_(4)]Cl`

Discussion

16.	Gases tend to behave non-ideally at low temperatures and high pressures. The deviation from ideal behaviour can be explained by considering two types of corrections. They are volume correction and pressure correction. Select incorrect statement(s) :
Answer» a)Volume correction is DUE to finite size of MOLECULES and pressure correction is due to force of ATTRACTION between molecules b)At high temperatures, molecules have greater kinetic energy, and attractive forces are smaller and the behaviour of gases is CLOSE to the ideal gas behaviour c)Volume correction is also called covolume or excluded volume and is four times the volume of spherical molecules present in ONE mole of the gas d)At very low pressure, force of attraction is effective and pressure correction needs further resolution. Answer :D

Discussion

17.	Give an example of Hinsberg test.
Answer» SOLUTION :`C_6H_5SO_2Cl + RNH_2 rarr C_6H_5SO_2NHR` TERTIARY amines do not react with Hinsberg reagent because they do not have HYDROGEN atom ATTACHED to nitrogen.

Discussion

18.	Gases released in reaction (I) and (II) are:
Answer» `CO_(2)CO_(2)` `SO_(2),NO_(2)` `SO_(2),CO_(2)` `SO_(2),NO` SOLUTION :N//A

Discussion

19.	Gases referred to as "greenhouse gases" are
Answer» `CO_2, O_2, NO_2,NH_3` Chlorofluoro carbon,`CO_2, NH_3 , N_2` `CH_4, N_2, CO_2, NH_3` Chlorofluoro carbon , `CO_2,CH_4, NO_2` Solution :These GASES CAUSE global WARMING of ATMOSHPERE which is called 'GREEN house effect', and these gases are called green house gases.

Discussion

20.	Give an example of heterogenous catalyst.
Answer» SOLUTION : Combination of `H_2` and `O_2` is CATALYSED by FINELY divided Pt ` 2H_2O (G) + O_2 (g)OVERSET("finely divided ")(to) 2H_2O (g)`

Discussion

21.	Gases like NH_(3), SO_(3) and CO_(2)are ........... as have greater Van der Waals force of attraction.
Answer» SOLUTION :EASILY LIQUEFIABLE

Discussion

22.	Gases liberated when Cu and Zn react with dil. HNO_(3) separately
Answer» `NO, NO_(2)` `N_(2)O, NO_(2)` `NO, N_(2)O` `NO_(2), N_(2)O` ANSWER :3

Discussion

23.	Give an example of hcp and bcc crystals.
Answer» SOLUTION :Be, Mg, TI, Zr etc show HCP. Al, Ni, CU, Ag, Pt, etc show ccp (fee). ‘

Discussion

24.	Gases possess characteristic critical temperature which depends upon the magnitude of intermolecular forces between the particles. Following are the critical temperatures of some gases. {:("Gases",H_(2),He,O_(2), N_(2)),("Critical temperature in Kelvin",33.2,5.3,154.3,126):} From the above data what would be the order of liquefaction of these gases? Start writing the order from the gas liquefying first.
Answer» `H_(2), He, O_(2) , N_(2)` `He, O_(2) , H_(2) , N_(2)` `N_(2, O_(2) , He , H_(2)` `O_(2) , N_(2) , H_(2) , He ` Solution :HIGHER the critical temperature,more easily is the gas LIQUEFIED. HENCE order of liquefication `: O_(2) , N_(2) , H_(2) , He`.

Discussion

25.	Give an example of Gomberg reaction.
Answer» Solution :The reaction of benzenediazonium SALTS with benzene or BROMOBENZENE or NITROBENZENE in aqueous alkali to afford the CORRESPONDING biphenyl DERIVATIVE is called Gomberg reaction.

Discussion

26.	Gases deviate from ideal gas behaviour because their molecules :
Answer» Possess negligible volume Have forces of ATTRACTION between them Are polyatomic All of these Answer :B

Discussion

27.	Give an example of elastomers .
Answer» SOLUTION :Buna-S, Buna-N and NEOPRENE

Discussion

28.	Gases deviate from ideal behaviour at high pressures. Which of the following is correct for non-ideality at high pressure :
Answer» 1. the collisions between the molecules BECOMES enormous 2. the GAS molecules MOVE only in ONE direction 3. the VOLUME of the gas becomes insignificant 4. intermolecular interactions become significant Answer :D

Discussion

29.	Gases deviate from ideal behaviour at high pressure because at high pressure :
Answer» 1. size of the molecules BECOME considerably large 2. molecules become STATIONARY 3. rate of MOLECULAR collisions become ENORMOUS 4. intermolecular forces become enormous. Answer :D

Discussion

30.	Give an example of elastomer.
Answer» SOLUTION :NATURAL RUBBER or Buna-S or Buna-N or NEOPRENE.

Discussion

31.	Gases C and D are
Answer» `SO_(2),SO_(3)` `SO_(3),CO_(2)` `NO_(2),MgO` `ZnO,SO_(3)` Solution :(A) is `FeSO_(4).7H_(2)O` `FeSO_(4)+BaCl_(2)tounderset((B))(BaSO_(4)darr)+FeCl_(2)` `2FeSO_(4)overset(Delta)tounderset((E))(Fe_(2)O_(3))+underset((C))(SO_(2))+underset((D))(SO_(3))` `Fe_(2)O_(3)+6HCl tounderset((F))(2FeCl_(3))+3H_(2)O` `2FeCl_(3)+H_(2)Stounderset((H))(2FeCl_(2))+2HCl+underset((G))(S)` `2FeCl_(3)+SnCl_(2)to 2FeCl_(2)+SnCl_(4)` `4FeCl_(3)+3K_(4)FE(CN)_(6)tounderset("Prussian blue")(Fe_(4)[Fe(CN)_(6)]_(3))+12KCl`

Discussion

32.	Give an example of disproportionation reaction.
Answer» Solution :Coper (I) salts decompose in water.HALF the Cu(I) changesto copper metal and the other half to copper (II), i.e., `2CU^(+)rarr Cu+Cu^(2+)`. This is KNOWNAS disproportionation.

Discussion

33.	Gases are effusing out through a pin hole of a container containing gas mixture of H_(2), He and CH_(4). What should be the composition of the gas mixture, so that in the initial fom, gas mixture effused out will have equal compositions for all gases?
Answer» `1:2:8` `7:10:20` `1.414:2:4` NONE of the above Answer :B::C

Discussion

34.	What is meant by 'disproportionation'? Give anexample of disproportionation reaction in aqueous solution.
Answer» Solution :Decomposition of copper (1) salts in water is an EXAMPLE of DISPROPORTIONATION reaction where half of the Cu(I) changes to copper metal and the other half to copper (II). `2Cu^(+) rarr Cu + Cu^(2+)` or`3MnO_(4)^(2-) + 4H^(+) rarr 2MnO_(4)^(-) + MnO_2 + 2H_2O`

Discussion

35.	Gaseous hydrocarbon gives upon combustion 0.72g of water and 3.08g of CO_(2). The empirical formula of the hydrocarbon is
Answer» `C_(2)H_(4)` `C_(3)H_(8)` `C_(6)H_(5)` `C_(3)H_(7)` ANSWER :D

Discussion

36.	Gaseous HCl is a poor conductor or electricity while its aqueous solution is a good conductor this is because
Answer» `H_(2)O` is a GOOD conductor of electricity a gas cannot conduct electrieity but a liquid can HCl gas does not obey Ohm's LAW, whereas the solution does HcI IONISES in aqueous solution Solution :In gaseous state the HCl is covalent in nature WHITE in aqueous solution it ionises to give `H^(+) and Cl^(-)` ions.

Discussion

37.	Give an example of disproportionation reaction
Answer» SOLUTION :Decomposition of COPPER (1) salts in water is an example of disproportionation reaction where half of the CU(I) changes to copper METAL and the other half to copper (II). `2Cu^(+) RARR Cu + Cu^(2+)` or`3MnO_(4)^(2-) + 4H^(+) rarr 2MnO_(4)^(-) + MnO_2 + 2H_2O`

Discussion

38.	Give an example of coordination isomerism.
Answer» SOLUTION :`[CR(NH_(3))_(6)][CoF_(6)] and [CO(NH_(3))_(6)][CrF_(6)]`

Discussion

39.	Give an example of denatured protein.
Answer» Answer :Proteins are biologically ACTIVE in their NATURAL STATE. On treatment with strong mineral acid or base, they undergo DENATURATION. i.e., Denaturation of the yolk of egg after heating.

Discussion

40.	Gaseous HCl is a poor conductor of electricity while its aqueous solution is a good conductor this is because
Answer» `H_2O` is a good conductor of electricity A gas cannot conduct electricity but a LIQUID can HCl gas does not obey Ohm.s law WHEREAS the SOLUTION does HCl ionises in aqueous solution Answer :D

Discussion

41.	Give an example of complex of the type [Ma_2b_2c_2] where a,b,c are monodentate ligands and give the possible isomers.
Answer» Solution :Example for ` [Ma_2, b_2, C_2] ` where a,b,c, are the complex MONODENTATE ` [CR(NH_3) _2C1_2Br_2 ]^(-1) `

Discussion

42.	Gaseous decomposition of A follows Ist order kinetics . Pure A (g) is taken in a sealed flask where decomposition occurs as A(g) to 2B(g) + C(g) After 10 sec., a leak was developed in the flask. On analysis of the effused gaseous mixture (Obeying Graham's law ) coming out initially moles of B(g) were found to be double of A. What is rate constant in "sec"^(-1). Given : Molecular weight of A = 16, Molecular weight of B =4 , Molecular weight of C=8 [In 3 =1.1,In 2 = 0.7] [Write your answer by multiplying it with 100.]
Answer» ANSWER :4

Discussion

43.	Gaseous benzene reacts with hydrogen gas in presence of a nickel catalyst to form gaseous cyclohexane according to the reaction: C_(6)H_(6)(g)+3H_(2(g)) rarr C_(6)H_(12(g)) A mixture of C_(6)H_(6) and excess H_(2) has a pressure of 60 mm of Hg in an unknown volume. After the gas has been passed over a nickel catalyst and all the benzene converted to cyclohexane. the pressure of the gas was 30 mm of Hg in the same volume and temperature. The fraction of C_(6)H_(6) (by volume) present in the original volume is:
Answer» `1//3` `1//4` `1//5` `1//6` Solution :Suppose INITIALLY, pressure of `C_(6)H_(6)(G) =P_(1) mm and" that of "H_(2)(g) =P_(2) mm` `THEREFORE P_(1)+P_(2)=60 mm"….(1)"` After the reaction Pressure of `C_(6)H_(6)(g)=0` Pressure of `H_(2)(g)=P_(2)-3P_(1)` Pressure of `C_(6)H_(12)(g)=P_(1)` Total pressure `=P_(2)-3P_(1)+P_(1)=30 mm` Or, `P_(2)-2P_(1)=30 mm"....(2)"` Solving (1) & (2) we GET `P_(1)=10 mm` `P_(2)=50 mm` Fraction of `C_(6)H_(6)(g)` volume = Fraction of moles = Fraction of pressure `=(10)/(60)=(1)/(6)` Hence, (D) is the CORRECT answer.

Discussion

44.	Giveanexampleof coordinationcompound usedin medicine.
Answer» SOLUTION :MEDICAL usesof coordinationcompounds (i) `Ca-EDTA` chelateis usedin the treatmentof LEAD andradioactivepoisoning.Thatis forremove leadand radiactivemetalionsfromthe BODY (ii) Cis- platinis usedmetalionsfromthe body.

Discussion

45.	Gas X and Gas Y in solution state react to give a turns substance Z. X has unpleasant odour and turns lead acetate paper black. In the first reaction X is oxidised and Y is reduced. Y on further oxidation with O_(3) gives a compound W In which of the following reactions also the above turbidity (Z) is seen
Answer» `K_(2)Cr_(2)O_(7)+Na_(2)SO_(3) OVERSET"acidic medium"rarr` `Na_(2)S_(2)O_(3)+Cl_(2)+H_(2)Orarr` `SCl_(4)+H_(2)Orarr` `SO_(2)+H_(2)O_(2)rarr` ANSWER :B

Discussion

46.	Gasthatturns lime watermilky and aciddied K_(2)Cr_(2)O_(7) green is (a) ____.
Answer» ANSWER :a.`SO_(2)`

Discussion

47.	Give an example of coordination compound used in medicine and two examples of biologically important coordination compounds.
Answer» Solution :Coordination compounds USED in medicine Cis-platin is used as antiumour DRUG in cancer treatement. EXAMPLES of biologically IMPORTANT coordination compounds. (i) ` Fe^(2+) ` -Porphyrin complex present in RBC a important role in respiraton (ii) ` Mg^(2+) ` porphyrin complex present in chlorophyll plays a important role in photosynthesis.

Discussion

48.	A gas which cannot be collected over water is
Answer» `N_2` `O_2` `SO_2` `PH_3` ANSWER :C

Discussion

49.	Gas needed by plants for their growth
Answer» `O_2` `N_2` `CO` `CO_2` ANSWER :D

Discussion

50.	Give an example of associated colloid.
Answer» SOLUTION :SOAPS and DETERGENTS.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Gasoline is obtained from crude petroleum oil by its

What is shape selective catalysis? Give an example of such type of catalyst.

Give an example of primary cell.

Give an example of network polymer.

Give an example of narcotic which is used as an analgesic.

Give an example of linkage isomerism.

Gasoline has compoundshaving composition

Give an example of linkage isomerism

Gasoline has composition

Give an example of ionization isomerism

Gases tend to behave non-ideally at low temperatures and high pressures. The deviation from ideal behaviour can be explained by considering two types of corrections. They are volume correction and pressure correction. Select incorrect statement(s) :

Give an example of Hinsberg test.

Gases released in reaction (I) and (II) are:

Gases referred to as "greenhouse gases" are

Give an example of heterogenous catalyst.

Gases like NH_(3), SO_(3) and CO_(2)are ........... as have greater Van der Waals force of attraction.

Gases liberated when Cu and Zn react with dil. HNO_(3) separately

Give an example of hcp and bcc crystals.

Give an example of Gomberg reaction.

Gases deviate from ideal gas behaviour because their molecules :

Give an example of elastomers .

Gases deviate from ideal behaviour at high pressures. Which of the following is correct for non-ideality at high pressure :

Gases deviate from ideal behaviour at high pressure because at high pressure :

Give an example of elastomer.

Gases C and D are

Give an example of disproportionation reaction.

Gases are effusing out through a pin hole of a container containing gas mixture of H_(2), He and CH_(4). What should be the composition of the gas mixture, so that in the initial fom, gas mixture effused out will have equal compositions for all gases?

What is meant by 'disproportionation'? Give anexample of disproportionation reaction in aqueous solution.

Gaseous hydrocarbon gives upon combustion 0.72g of water and 3.08g of CO_(2). The empirical formula of the hydrocarbon is

Gaseous HCl is a poor conductor or electricity while its aqueous solution is a good conductor this is because

Give an example of disproportionation reaction

Give an example of coordination isomerism.

Give an example of denatured protein.

Gaseous HCl is a poor conductor of electricity while its aqueous solution is a good conductor this is because

Give an example of complex of the type [Ma_2b_2c_2] where a,b,c are monodentate ligands and give the possible isomers.

Giveanexampleof coordinationcompound usedin medicine.

Gasthatturns lime watermilky and aciddied K_(2)Cr_(2)O_(7) green is (a) ____.

Give an example of coordination compound used in medicine and two examples of biologically important coordination compounds.

A gas which cannot be collected over water is

Gas needed by plants for their growth

Give an example of associated colloid.