94420 + Interview Questions in Chemistry in Class 12

1.	Amine are more basic than :
Answer» ALCOHOLS Ethers Esters All Answer :D

Discussion

2.	Amides with no substitution on nitrogen react with tht: solution of bromine or chlorine in NaOH or KOH to yield aminei through a reaction called as Hofmann's degradation. R-overset(O)overset(\|\|)(C )-NH_(2)+Br_(2)+4NaOH overset(H_(2)O)rarr R-NH_(2)+2NaBr+Na_(2)CO_(3)+2H_(2)O Amides can be reduced to amines having same number of carbon atoms R-overset(O)overset(\|\|)C-NH_(2)-underset(LiAlH_(4))overset([H])toR-CH_(2)-NH_(2) Carbon dioxide gas is released in above mentioned reaction
Answer» 1 Answer :A

Discussion

3.	Amineare basic is natureaccording to
Answer» Arrhenioustheory LEWIS THEORY Lowary - Bronstedtheroy all of these ANSWER :D

Discussion

4.	Amides with no substitution on nitrogen react with tht: solution of bromine or chlorine in NaOH or KOH to yield aminei through a reaction called as Hofmann's degradation. R-overset(O)overset(\|\|)(C )-NH_(2)+Br_(2)+4NaOH overset(H_(2)O)rarr R-NH_(2)+2NaBr+Na_(2)CO_(3)+2H_(2)O Amides can be reduced to amines having same number of carbon atoms R-overset(O)overset(\|\|)C-NH_(2)-underset(LiAlH_(4))overset([H])toR-CH_(2)-NH_(2) Benzamide when treated with Br_(2) in presence of NaOH gives aniline.
Answer» 1 Answer :A

Discussion

5.	Amides on treatment with Br_2 and KOH form the amines having the underline(" same number of carbon atoms").
Answer» Solution :Amides on TREATMENT with Br2 and KOH FORM the amines having LESS NUMBER of carbon ATOMS.

Discussion

6.	Amides may be converted into amines by reaction named after
Answer» Perkin Claisen Hofmann Kolbe Answer :C

Discussion

7.	Amides may be converted into amines by reaction named after :
Answer» Perkin Claisen Hofmann Kekule Answer :C

Discussion

8.	Amides are least reactive of the acid derivatives towards_____reactions.
Answer» SOLUTION :NUCLEOPHILIC ACYL SUBSTITUTION.

Discussion

9.	Amides can be converted into amines by
Answer» HOFFMANN bromamide reaction Perkin's reaction Claisen SCHMIDT codensation All the above methods Answer :A

Discussion

10.	Amino acids are amphoteric in nature. Explain.
Answer» SOLUTION :Amides behave both as weak acid as well as weak base and thus show AMPHOTERIC character. This can be proved by the following reactions. Acetamide (as base) reacts with hydrochloric acid to form salt `underset("Acetamide")(CH_(3)-overset(O)overset(\|\|)(C)-NH_(2))+HCl tounderset("Acetamide hydrochloride")(CH_(3)-overset(O)overset(\|\|)(C)-overset(+)(NH_(3))Cl^(-))` Acetamide (as acid) reacts with SODIUM to form sodium salt and hydrogen GAS is liberated. `underset("Acetamide")(2CH_(3)-overset(O)overset(\|\|)(C)-NH_(2))+Natounderset("Sodium acetamide")(2CH_(3)-overset(O)overset(\|\|)(C)-overset(+)(NH)Na)+H_(2)`

Discussion

11.	Amides are:
Answer» AMPHOTERIC ACIDIC Basic Netural Answer :A

Discussion

12.	Amide linkage is absent is
Answer» NYLON -6 Nylon -66 Nylon -2- Nylon -6 PHBV ANSWER :D

Discussion

13.	Amide group is present in
Answer» Lipids Carbohydrates Amino acids PROTEINS Solution :In proteins AMIDE group is PRESENT `(-NH-underset(R)underset(\|)(C)H-ubrace(underset(O)underset(\|\|)(C)-NH-underset(R)underset(\|)(C)H)_("Amide orppeptide BOND")-underset(O)underset(\|\|)(C)-)_(n)`

Discussion

14.	(a)Me_(3)CCH_(2)CH(Cl)Ph., (b)MeC(Et)_(2)CH_(2)Cl (c)MeCH=C(Br)CH_(2)Me_(2),(d)m-ClC_(6)H_(4)CH_(2)CHMe_(2) (e)p-I-C_(6)H_(4)CH(Me)Et (f)p-FCH_(2)C_(6)H_(4)CH_(2)Cme_(3) (g)MeCH=CHC(Cl)Me_(2),(h)MeC(Br)(et)Et (i)MeCH=CHc(Cl)Me_(2),(j)EtC(Me)_(2)CH_(2)Br (k)Me_(2)CHCH(Br)Me ,(L)BRCH_(2)C-=CCH_(2)Cl (m)CHF_(2)BrClF ,(n)(CBr_(3))_(3)CBr) (o)MeC(p-BrC_(6)H_(4))_(2)CH(Cl)Me ,(p)Me_(3)CCH=ClC_(6)H_(4)Cl-m
Answer» SOLUTION :

Discussion

15.	(a)Metallurgy-Extraction of metals(b)Clay-Ore of Al (C )Na-Native element (d)Ore-Gangue
Answer» SOLUTION :(a)Metallurgy-Extraction of METALS

Discussion

16.	Amatol is blasting material which is obtained by mixing TNT with
Answer» `NH_(4)Cl`<BR>`NH_(4)Br` `NH_(4)NO_(3)` `(NH_(4))_(2) SO_(4)` SOLUTION :`NH_(4)NO_(3)`

Discussion

17.	Amalgams are:
Answer» Always solid Highly coloured alloys Alloys which contain MERCURY as ONE of the contents COMPOUNDS of mercury ANSWER :C

Discussion

18.	Find out the incorrect pair (a)Magnetite-Fe_(3)O_(4) (b)Malachite-CuCO_(3).Cu(OH)_(2) (c )Horn silver-Ag_(2)S (d)Stefinite-Ag_(2)SbS_(4)
Answer» SOLUTION :(C )Horn silver-`Ag_(2)S`

Discussion

19.	A_(m)^(@) value cannot be determined by extraploting, the plot between A_(m) verses C^(1//2) for the compound.
Answer» `KCl` `K_(2)SO_(4)` `NH_(4)OH` `NaNO_(3)` SOLUTION :It is not applicable for weak ELECTROLYTE.

Discussion

20.	(A)Lyophilic colloids are called as reversible sols.(R ) Lyophilic sols are liquid loving .
Answer» Both (A) and (R ) are TRUE and (R ) is the correct explanation of (A) Both (A)and (R ) are true and (R ) is not the correct explanation of (A) (A) is true but (R ) is FALSE Both (A) and (R ) are false Answer :B

Discussion

21.	Aluminothermy used for the spot welding of large iron sturctures is based upon the fact that
Answer» As COMPARED to IRON, aluminium has greater AFFINITY for oxygen As compared to aluminium, ironhas greater affinity for oxygen Reaction between aluminium and oxygen is ENDOTHERMIC Reaction between iron oxide and alumi-nium is endothermic Answer :A

Discussion

22.	Aluminothermy used for the spot welding of large iron structures is based upon the fact that :
Answer» As compared to IRON, aluminium has GREATER AFFINITY for OXYGEN As compared to aluminium, iron has greater affinity for oxygen Reaction between aluminium and oxygen is endothermic Reaction between iron OXIDE and aluminium is exothermic Answer :A::D

Discussion

23.	Aluminothermic process is usedinthe metallurgy of
Answer» Pb Ag Cr None of these Answer :C

Discussion

24.	Aluminothermic process is used for the extraction of metals whose oxides are :
Answer» fusible not easily REDUCED by CARBON not easily reduced by hydrogen STRONGLY basic. Solution :Since the METAL oxides have high melting points, their reduction by carbon is not satisfactory.

Discussion

25.	Aluminothermic process is used for the extraction of metals, whose oxides are :
Answer» Fusible Not EASILY redused by carbon Not easily REDUCED by hydrozen Strongly basic Answer :B

Discussion

26.	Orford process is used in extraction of:
Answer» ANSWER :B

Discussion

27.	Alumino-thermy is a process involving :
Answer» REDUCTION of OXIDE of a metal by HEATING with sodium Exothermic reduction reduction of metal OXIDES by heating with Al Reduction of oxides of a metal by heating with carbon None of these Answer :B

Discussion

28.	Aluminothermic process is used for the extraction of metals, whose oxides are
Answer» FUSIBLE not easliy REDUCED by carbon not EASILY reduced by hydrogen strongly basic Answer :B

Discussion

29.	Alumino-thermic process is used for metallurgy of
Answer» Pb Ag Al None of these Answer :D

Discussion

30.	Aluminium vessels should not be washed with materials containing washing soda because :
Answer» Washing soda is expensive Washing soda is easily decomposed Washing soda REACTS with aluminium to from SOLUBLE aluminate Washing soda reacts with aluminium to form INSOLUBLE aluminium oxide Answer :C

Discussion

31.	Aluminium vesselsshouldnot be washed with material containing washing soda because
Answer» WASHINGSODA reactswith aluminium to FORM solublemeta-aluminate. WASHING soda is expensive washing soda is easilydecomposed washing soda reactswithaluminium to forminsolublealuminium oxide Solution :` 2AI + Na_(2)CO_(3) + 3H_(2)O to 2NaAlO_(2) + CO_(2) + 3H_(2) NaAIO_(2)`is sodium meta- aluminate WHICHIS SOLUBLEIN water.

Discussion

32.	Aluminiumsulphate (X) is slightlyinsoluble in water it isconvertedintosolublesulphateby using Na_(2)CO_(3) in theprecipitateof sodiumcarbonateextract .Moleof Na_(2)CO_(3)required forconplateconversionof 1 moleof (X) intosolubleis
Answer» `1` `2` `3` `4` Answer :C

Discussion

33.	Aluminiumreacts with NaOH and forms compound 'X'. If the coordination number of aluminium in 'X' is 6, the correct formula of X is
Answer» `[Al(H_(2)O)_(4)(OH)_(2)]^(+)` `[Al(H_(2)O)_(3)(OH)_(3)]` `[Al(H_(2)O)_(2)(OH)_(4)]^(-)` `[Al(H_(2)O)_(6)(OH)_(3)]` Answer :C

Discussion

34.	Aluminium oxide may be electrolysed at 1000^(@)C to furnish aoluminium metal (At. Mass=27amu,1 faraday=96,500) Al^(3+)+3e^(-)toAl^(0) To prepare 5.12 kg of aluminium metal by this method would require
Answer» `5.49xx10^(7)C` of electricity `1.83xx10^(7)C` of electricity `5.49xx10^(4)C` of electricity `5,49xx10^(1)C` of electricity Solution :27 gm of Al is obtained by PASSING a CURRENT of `3xx96500C` `because` gm of Al is obtained by passing a current of `3xx(96500)/(27)C`. `therefore5.12xx10^(3)gm` of Al is obtained by passing a current of `3xx(96500)/(27)xx5.12xx1000` `=1.83xx10^(7)Cxx3=5.49xx10^(7)C`.

Discussion

35.	Aluminium oxide may be electrolysed at 100^(@)C to furnish aluminium metal (atomic mass=27 amu). The cathodic reaction is : Al^(3+)+3e^(-) to Al To prepare 5.12 kg of aluminium metal by this reaction would require :
Answer» `549xx10^(7)" C"` of electricity `1.83xx10^(7)" C"` of electricity `5.49xx10^(7)" C "` of electricity `5.49xx10^(10)" C "` of electricity Solution :(c ) `AL^(3+)+underset(3xxF)3e^(-) to underset(27G)Al` To deposit 27 G of Al metal, electricity needed `=3xxF` To deposit 5120 g of Al metal, electricity needed `=(3F)/((27 g))xx(5120 g)` `=568.89 F=5.49xx10^(7)" C "`

Discussion

36.	Aluminium oxide contains 52.9% aluminium and carbon dioxide contains 27.27% carbon. Assuming the validity of the law of reciprocal proportions , calculate the percentage of aluminium in aluminium carbide.
Answer» Solution :From the DATA, it is observed that the RATIO of masses of ALUMINIUM and carbon in aluminium carbide should be 3:1 or its simple multiple, Hence, percentage of aluminium in aluminium carbide `=(3)/(4)xx100=75.0`

Discussion

37.	Aluminium metals is frequecntly used as areducingagent for theextractionof metals suchas chromium or manganese from thetheirrespectiveoxides , why ?
Answer» ANSWER :N//A

Discussion

38.	Aluminium metal reacts with alcohol gives
Answer» ROAL `(RO)_2Al` `(RO)_3Al` RCOAl Answer :C

Discussion

39.	Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same ? (i) Good thermal conductivity (ii) Good electrical conductivity (iii) Ductility (iv) High melting point
Answer» IONIC solids Covalent solids METALLIC solids MOLECULAR solids ANSWER :C

Discussion

40.	Aluminium is used for making alloys because of its ___________
Answer» RESISTANCE to corrosion poor conductivity heaviness all of these Answer :A

Discussion

41.	Aluminium is stable in air and water inspite of the fact that it is reactive metal. The reason is that a thin film of its oxide is formed on its surface which useful that in industry, it is purposely deposited by an electrolytic process called anodising. Reaction of aluminium with oxygen is highly exothermic and is called thermicreaction. 2Al(s)+3//2O_(2)(g)toAl_(2)(s),DeltaH=-1670kJ Thermite reaction finds applications in the metallurgical attraction of many metals form theri oxides and for welding of metals. The drawback is that to start the reaction, high temperature is required for whcih an ignition mixture is used. The reaction which is not involved in thermite process:
Answer» `3Mn_(3)O_(4)+8Al to 9Mn+4Al_(2)O_(3)` `Cr_(2)O_(3)+2AL to 2Cr+Al_(2)O_(3)` `2Fe+Al_(2)O(3) to Fe_(2)O_(3)+2Al` `B_(2)O_(3)+2Al to 2B+Al_(2)O_(3)` Answer :C

Discussion

42.	Aluminium is stable in air and water inspite of the fact that it is reactive metal. The reason is that a thin film of its oxide is formed on its surface which useful that in industry, it is purposely deposited by an electrolytic process called anodising. Reaction of aluminium with oxygen is highly exothermic and is called thermicreaction. 2Al(s)+3//2O_(2)(g)toAl_(2)(s),DeltaH=-1670kJ Thermite reaction finds applications in the metallurgical attraction of many metals form theri oxides and for welding of metals. The drawback is that to start the reaction, high temperature is required for whcih an ignition mixture is used. Anodising can be done be electrolysing dilute H_(2)SO_(4) with aluminium as anode. This results in:
Answer» The formation of `Al_(2)(SO_(4))_(3)` on ther surface of aluminium anode The formation of OXIDE film `(Al_(2)O_(3))` on the surface of aluminium anode The formation of POLYMERIC aluminium hydride film on the surface of aluminium anode None of the above Answer :B

Discussion

43.	Aluminium is produced on a large scale by electrolysis of alumina, dissolved in fused cryolite and a little fluorspar are respectively ___________.
Answer» `Na_(3)AIF_(6)` and `CaF_(2)` `AlF_(3)` and KF `Al_(2)O_(3)` and KCL `KCl.MgCl_(2).6H_(2)O` and `MgF_(2)` Answer :A

Discussion

44.	Aluminium is producedby theelectrolysisof …I ..in the presence of …ii… fill in theblanks I & II with appropriate words
Answer» I aluminium oxide II zeolite I aluminium chloride, iii CRYOLITE I aluminium oxide ii cryolite aluminium chloride, ii zeolite Solution :ALUMINIUMIS produced by electrolysis of aluminium oxide in the presence of cryolite

Discussion

45.	Aluminium is not present in which of the following mineral :
Answer» Cryolite Fledspar Fluorspar Mica Answer :C

Discussion

46.	Aluminium is not used :
Answer» In THERMITE welding As OXIDISER in metallurgy For MAKING utensils In SILVERY paints Answer :B

Discussion

47.	Aluminium is not used
Answer» In silvery paints For making utensils As a REDUCING involves As oxidizer in METALLURGY SOLUTION :Aluminium is USED as reducing agent in metallurgy.

Discussion

48.	Aluminium is obtained by :
Answer» REDUCING `Al_2O_3` with coke electrolysing `Al_2O_3` dissolved in `Na_3AlF_6` reducing `Al_2O_3` with Cr heating `Al_2O_3` with CRYOLITE . ANSWER :B

Discussion

49.	Aluminium is more reactive than Fe. But Al is less easily corroded than iron because
Answer» Al is NOBLE metal Iron forms both mono and divalent ions Oxygen forms a protective oxide LAYER Fe undergoes reaction EASILY with `H_(2)O` Solution :Aluminium forms a protective oxide layer but iro does not.

Discussion

50.	Aluminium is more reactive than iron. But aluminium is less easily corroded than iron because.
Answer» OXYGEN forms a protective oxide layer Aluminium is a noble metal Iron UNDERGOES reaction EASILY with WATER Iron forms both mono and divalent ions Answer :A

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Amine are more basic than :

Amineare basic is natureaccording to

Amides on treatment with Br_2 and KOH form the amines having the underline(" same number of carbon atoms").

Amides may be converted into amines by reaction named after

Amides may be converted into amines by reaction named after :

Amides are least reactive of the acid derivatives towards_____reactions.

Amides can be converted into amines by

Amino acids are amphoteric in nature. Explain.

Amides are:

Amide linkage is absent is

Amide group is present in

(a)Metallurgy-Extraction of metals(b)Clay-Ore of Al (C )Na-Native element (d)Ore-Gangue

Amatol is blasting material which is obtained by mixing TNT with

Amalgams are:

Find out the incorrect pair (a)Magnetite-Fe_(3)O_(4) (b)Malachite-CuCO_(3).Cu(OH)_(2) (c )Horn silver-Ag_(2)S (d)Stefinite-Ag_(2)SbS_(4)

A_(m)^(@) value cannot be determined by extraploting, the plot between A_(m) verses C^(1//2) for the compound.

(A)Lyophilic colloids are called as reversible sols.(R ) Lyophilic sols are liquid loving .

Aluminothermy used for the spot welding of large iron sturctures is based upon the fact that

Aluminothermy used for the spot welding of large iron structures is based upon the fact that :

Aluminothermic process is usedinthe metallurgy of

Aluminothermic process is used for the extraction of metals whose oxides are :

Aluminothermic process is used for the extraction of metals, whose oxides are :

Orford process is used in extraction of:

Alumino-thermy is a process involving :

Aluminothermic process is used for the extraction of metals, whose oxides are

Alumino-thermic process is used for metallurgy of

Aluminium vessels should not be washed with materials containing washing soda because :

Aluminium vesselsshouldnot be washed with material containing washing soda because

Aluminiumsulphate (X) is slightlyinsoluble in water it isconvertedintosolublesulphateby using Na_(2)CO_(3) in theprecipitateof sodiumcarbonateextract .Moleof Na_(2)CO_(3)required forconplateconversionof 1 moleof (X) intosolubleis

Aluminiumreacts with NaOH and forms compound 'X'. If the coordination number of aluminium in 'X' is 6, the correct formula of X is

Aluminium oxide may be electrolysed at 1000^(@)C to furnish aoluminium metal (At. Mass=27amu,1 faraday=96,500) Al^(3+)+3e^(-)toAl^(0) To prepare 5.12 kg of aluminium metal by this method would require

Aluminium oxide may be electrolysed at 100^(@)C to furnish aluminium metal (atomic mass=27 amu). The cathodic reaction is : Al^(3+)+3e^(-) to Al To prepare 5.12 kg of aluminium metal by this reaction would require :

Aluminium oxide contains 52.9% aluminium and carbon dioxide contains 27.27% carbon. Assuming the validity of the law of reciprocal proportions , calculate the percentage of aluminium in aluminium carbide.

Aluminium metals is frequecntly used as areducingagent for theextractionof metals suchas chromium or manganese from thetheirrespectiveoxides , why ?

Aluminium metal reacts with alcohol gives

Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same ? (i) Good thermal conductivity (ii) Good electrical conductivity (iii) Ductility (iv) High melting point

Aluminium is used for making alloys because of its ___________

Aluminium is produced on a large scale by electrolysis of alumina, dissolved in fused cryolite and a little fluorspar are respectively ___________.

Aluminium is producedby theelectrolysisof …I ..in the presence of …ii… fill in theblanks I & II with appropriate words

Aluminium is not present in which of the following mineral :

Aluminium is not used :

Aluminium is not used

Aluminium is obtained by :

Aluminium is more reactive than Fe. But Al is less easily corroded than iron because

Aluminium is more reactive than iron. But aluminium is less easily corroded than iron because.