94420 + Interview Questions in Chemistry in Class 12

1.	Aromatic properties of benzene are proved by
Answer» AROMATIC SEXTET theory Resonance theory Molecular ORBITAL theory All of these Answer :D

Discussion

2.	Aromatic primary amines can be distinguished from aliphatic primary amines by :
Answer» Tollen's TEST Carbylamine test AZO dye test Action on red LITMUS paper. Answer :C

Discussion

3.	Aromatic primary amine when treated with cold HNO_2 and HCl forms
Answer» benzene diazonium salt nitrobenzene benzyl alcohol Answer :B

Discussion

4.	Aromatic ketones can be obtained from benzene using
Answer» FRIEDEL CRAFTS alkylation Friedel Crafts acylation. Reimer Tiemann Cannizzaro's reaction. Answer :B

Discussion

5.	Aromatic compounds undergo Friedel-Craft reaction in presence of anhydrous _____.
Answer» ANSWER :`AlCl_3`

Discussion

6.	Aromatic compounds burn with sooty flame because
Answer» They have a ring structure of CARBON atoms They have a relatively HIGH percentage of hydrogen They have a relatively high percentage of carbon They RESIST reaction with oxygen of AIR SOLUTION :They have a relatively high percentage of carbon

Discussion

7.	Aromatic ________can be prepared by vigorous oxidation of alkyl benzenes with chromic acid.
Answer» SOLUTION :CARBOXYLIC ACIDS

Discussion

8.	Aromatic _____ are most widely used in dyeing industry.
Answer» ANSWER :AMINES.

Discussion

9.	Aromatic and aliphatic hydroxy compound have _____ properties . (Similar, Dissimilar )
Answer» ANSWER :DISSIMILAR.

Discussion

10.	Aromatic amino compounds are called _____ .
Answer» Phenols ANILINES Alkyl amines Arenamines Answer :Anilines

Discussion

11.	Aromatic amines are weaker bases than aliphatic amines. Why?
Answer» SOLUTION :The basic character of AMINES is due to presence of a LONE pair of electrons on N-atom. Aromatic amines have RESONANCE structure and lone pair of electrons becomes less AVAILABLE for co-ordination. No such resonance exists in aliphatic amines and lone pair is easily available. Hence aromatic amines are weaker bases than aliphatic amines.

Discussion

12.	Account for the following Aromatic amines are weaker bases than aliphatic amines.
Answer» SOLUTION :Because aryl group is electron withdrawing which decreases electron DENSITY onnitrogen, MAKING them less BASIC whereas alkyl group is electron releasing which makes alkyl amines more basic.

Discussion

13.	Aromatic amines are important synthetic intermediates. Write down the isocyanide test for the primary amines.
Answer» Solution :When primary amine is HEATED with ALC, KOH and `CHCl_3` a foul SMELLING isocyanide is obtained. `C_6H_5NH_2+CHCl_3+3KOHrarr C_6H_5NC+3KCl+3H_2O`

Discussion

14.	Aqueous solution of which of the following acids cannot be kept in a bottle of glass
Answer» HF HCl HBr Hl Solution :HF is NORMALLY stored in METAL apparatus because HF attacks glass with the formation of fluorosilicates ions. `SiO_(2) +6HF to [SiF_(6)]^(2-)+ 2H^(+) +2H_(2)O`

Discussion

15.	Aromatic amines are important synthetic intermediates. How will you convert nitrobenzene to aniline?
Answer» SOLUTION :

Discussion

16.	Aqueous solution of which of the following acid can not be kept in glass bottle ?
Answer» HF HI HCL HBr Answer :A

Discussion

17.	Aromatic aldehydes react with primary amines to form
Answer» AMINO acids Schiff's base Pyrosole Pyridine Answer :B

Discussion

18.	Aqueous solution of which elements is coloured?
Answer» `TiCl_(2)` `ZnCl_(2)` `CdCl_(2)` `Hg_(2)Cl_(2)` Answer :A

Discussion

19.	Aromatic aldehydes in the presence of cyanide ions are converted into a acyloins. This reaction is known as
Answer» PERKIN's reaction Cannizzaro reaction Benzoin condensation Claisen condensation Answer :C

Discussion

20.	ArOH underset(H_(2)O)overset(NaOH)to ArO^(-)Na^(+) underset(-NaX)overset(R-X)to Ar-O-Ar+ NaX This reaction represent which of the following ?
Answer» LUCAS TEST Cumene test DOW process NONE of these Solution :None of these

Discussion

21.	Aqueous solution of weak acid and weak base is
Answer» ACIDIC Basic Neutral Either acidic or basic Answer :C

Discussion

22.	Arnnge the following In the decreaalng order of theh basic strength in aqueous solution : CH_(3)NH_(2),(CH_(3))NH, (CH_(3))_(3)N and NH_(3)
Answer» SOLUTION :`(CH_(3))_(2)NH gt CH_(3)NH_(2) gt (CH_(3))_(3)N` and `NH_(3)`.

Discussion

23.	Aqueous solution of which carbohydrate give a dark blue colour with a few drops of iodine solution
Answer» Sucrose Starch Glucose Fructose Answer :B

Discussion

24.	Aqueous solution of urea is 20% by mass of solution. Then the percentage of urea by mass of solvent is
Answer» 0.2 0.25 0.4 0.8 Answer :B

Discussion

25.	Ar.N_(2)Cl overset(dil.H_(2)SO_(4))toX+N_(2)+HCl where regarding X, correct statement is
Answer» dissolves in NaOH solution it liberates `H_(2)` with Na it is stronger ACID than acetic acid 1 and 2 Answer :D

Discussion

26.	ArH + R -overset(O)overset(\|\|)(C )-CI overset("Lewis acid")rarr Ar-overset(O)overset(\|\|)(C )-R+HCI is an example of
Answer» Friedel-Craft alkylation Friedel-Craft acylation Cannizzaro REACTION Claisen condensation Solution :`ArH + R-CO-CI OVERSET("ANHYD".AICI_(3))RARR Ar-CO-R+HCI` This reaction is Friedel-Craft's acylation.

Discussion

27.	Aqueous solution of urea is :
Answer» Acidic Alkaline Almost neutral Amphotrric Answer :C

Discussion

28.	Argon was discovered by:
Answer» Cavendish Lavoisier Rayleigh Thomson Answer :C

Discussion

29.	Aqueous solution of the following compound on electrolysis gives ethane
Answer» Acetic acid Acetamide POTASSIUM ACETATE Ethyl acetate Solution :`underset"Potassium acetate"(2CH_3COOK)+2H_2O overset"ELECTROLYSIS"to CH_3-CH_3+underset"Anode"(2CO_2)+underset"CATHODE"(2KOH +H_2)`

Discussion

30.	Argyrol is_______.
Answer» COLLOIDAL silver colloidal ANTIMONY colloidal gold milk of magnesia Answer :A

Discussion

31.	Aqueous solution of sodium silicate is :
Answer» Acidic Alkaline Neutral Insoluble Answer :B

Discussion

32.	Argon possesses
Answer» TRANSLATIONAL motion only translational + rotational motion translational + vibrational motion translational + rotational + vibrational motion Solution :Argon is a monoatomic GAS , thus its molecules can move in any DIRECTION in SPACE . Hence , it can have three independent MOTIONS (all translational) . Therefore , argon possesses only translational motion .

Discussion

33.	Argon possess_________ energy.
Answer» Translational Vibrational Rotational Intermolecular Solution :NOBLE GASES POSSES translational motion and translational ENERGY

Discussion

34.	Aqueoussolutionof sodiumacetaneand sodiumpropionateon electrolysisyields :
Answer» EHTANE butane propane all of these Answer :D

Discussion

35.	Argon is used in arc welding because of its
Answer» ability to LOWER the melting point of metal flammability low REACTIVITY with metal high CALORIFIC value Answer :C

Discussion

36.	Aqueous solution of sodium acetate is
Answer» Alkaline Neutral Weakly acidic Strongly acidic Answer :A

Discussion

37.	Aqueous solution of soap is :
Answer» ACID Base Neutral Amphoteric ANSWER :B

Discussion

38.	Argon is used
Answer» to obtain LOW temperature in high temperature welding in RADIOTHERAPY welding in radiotherapy for treatment of cancer Solution :Argon is used in producing INERT ATMOSPHERE during welding and EXTRACTING of variousmetals.

Discussion

39.	Aqueous solution of raw sugar when passed over beds of animal charcoal becomes ___________
Answer» SOLUTION :COLOURLESS

Discussion

40.	Aqueous solution of potash alum is:
Answer» alkaline ACIDIC neutral soapy Solution :It is acidic because of the hydrolysis of `Al_(2)(SO_(4))_(3)` according to the following REACTION. `Al_(2)(SO_(4))_(3) + 6H_(2)O to 2AL(OH)_(3) + 3H_(2)SO_(4)`

Discussion

41.	Argentite is an ore of :
Answer» Cu Ft Au Ag Answer :D

Discussion

42.	Aqueous solution of SO_2 reacts with H_2Sto precipitate sulphur. Here SO_2 act as :
Answer» Catalyst Reducing agent Oxidising agent Acid Answer :C

Discussion

43.	Aqueous solution of potash alum is :
Answer» Alkaline Neutral Acidic Soppy Answer :C

Discussion

44.	Aresenic drugs are mainly used in the treatment of
Answer» Cholera Typhoid Syphilis Jaundice Solution :ARSENIC DRUGS are POISONOUS for syphilis causing MICROBES.

Discussion

45.	Aqueous solution of PCl_(3) conducts electricitydue to the presence of
Answer» `HOCl` `HCL` `H_(3)PO_(4)` `H_(2)O` Answer :2

Discussion

46.	Argentite, a compound of silver, was treated with potassium cyanide solution. The product obtained has the formula
Answer» `KAg(CN)_(2)` `K_(2)Ag (CN)_(2)` `K_(2)Ag (CN)_(4)` `KAg (CN)_(4)` SOLUTION :`Ag_(2) S + 4KCN harr underset("argentocyanide")underset("POTASSIUM")(2KAg(CN)_(2))+K_(2)S` Hence, (A) is the correct answer.

Discussion

47.	Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthalein indicator only in presence of
Answer» TRANS - glycerol catechol cis-glycerol both (B) and (C) ANSWER :D

Discussion

48.	Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthaleinindicator only in presence of :
Answer» trans-glycerol catechol cis-glycerol both (B) and (C ) Solution :It FORMS a stable cyclic complex with POLYHYDROXY COMPOUNDS LIKE cis-glycerol, cathechol, etc. This HELPS in the release of `H^+` as `H_3O^+` and , therefore, boric acid acts as a strong acid and hence can be titrated with sodium hydroxide using phenolphthalein.

Discussion

49.	Argentite is a mineral of :
Answer» Au Pt Ag Cu Answer :C

Discussion

50.	Arenes on treatment with chlorine in presence of ferric chloride as a catalyst undergo what type of reaction ?
Answer» ELECTROPHILIC substitution Nucleophilic substitution Electrophilic addition Nucleophilic addition Answer :A

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Aromatic properties of benzene are proved by

Aromatic primary amines can be distinguished from aliphatic primary amines by :

Aromatic primary amine when treated with cold HNO_2 and HCl forms

Aromatic ketones can be obtained from benzene using

Aromatic compounds undergo Friedel-Craft reaction in presence of anhydrous _____.

Aromatic compounds burn with sooty flame because

Aromatic ________can be prepared by vigorous oxidation of alkyl benzenes with chromic acid.

Aromatic _____ are most widely used in dyeing industry.

Aromatic and aliphatic hydroxy compound have _____ properties . (Similar, Dissimilar )

Aromatic amino compounds are called _____ .

Aromatic amines are weaker bases than aliphatic amines. Why?

Account for the following Aromatic amines are weaker bases than aliphatic amines.

Aromatic amines are important synthetic intermediates. Write down the isocyanide test for the primary amines.

Aqueous solution of which of the following acids cannot be kept in a bottle of glass

Aromatic amines are important synthetic intermediates. How will you convert nitrobenzene to aniline?

Aqueous solution of which of the following acid can not be kept in glass bottle ?

Aromatic aldehydes react with primary amines to form

Aqueous solution of which elements is coloured?

Aromatic aldehydes in the presence of cyanide ions are converted into a acyloins. This reaction is known as

ArOH underset(H_(2)O)overset(NaOH)to ArO^(-)Na^(+) underset(-NaX)overset(R-X)to Ar-O-Ar+ NaX This reaction represent which of the following ?

Aqueous solution of weak acid and weak base is

Arnnge the following In the decreaalng order of theh basic strength in aqueous solution : CH_(3)NH_(2),(CH_(3))NH, (CH_(3))_(3)N and NH_(3)

Aqueous solution of which carbohydrate give a dark blue colour with a few drops of iodine solution

Aqueous solution of urea is 20% by mass of solution. Then the percentage of urea by mass of solvent is

Ar.N_(2)Cl overset(dil.H_(2)SO_(4))toX+N_(2)+HCl where regarding X, correct statement is

ArH + R -overset(O)overset(||)(C )-CI overset("Lewis acid")rarr Ar-overset(O)overset(||)(C )-R+HCI is an example of

Aqueous solution of urea is :

Argon was discovered by:

Aqueous solution of the following compound on electrolysis gives ethane

Argyrol is_______.

Aqueous solution of sodium silicate is :

Argon possesses

Argon possess_________ energy.

Aqueoussolutionof sodiumacetaneand sodiumpropionateon electrolysisyields :

Argon is used in arc welding because of its

Aqueous solution of sodium acetate is

Aqueous solution of soap is :

Argon is used

Aqueous solution of raw sugar when passed over beds of animal charcoal becomes ___________

Aqueous solution of potash alum is:

Argentite is an ore of :

Aqueous solution of SO_2 reacts with H_2Sto precipitate sulphur. Here SO_2 act as :

Aqueous solution of potash alum is :

Aresenic drugs are mainly used in the treatment of

Aqueous solution of PCl_(3) conducts electricitydue to the presence of

Argentite, a compound of silver, was treated with potassium cyanide solution. The product obtained has the formula

Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthalein indicator only in presence of

Aqueous solution of orthoboric acid can be titrated against sodium hydroxide using phenolphthaleinindicator only in presence of :

Argentite is a mineral of :

Arenes on treatment with chlorine in presence of ferric chloride as a catalyst undergo what type of reaction ?