94420 + Interview Questions in Chemistry in Class 12

1.	Pb and Sn are exerted from their chief ores by:
Answer» CARBON REDUCTION and SELF reduction. Self reduction and carborn reduction. Electrolysis and self reduction. Self reduction and electrolysis Answer :B

Discussion

2.	Method of formation of solutionis given in Column I. Match it with the type of solution given in Column II. {:("Comumn I","ColumnII"),((i)"Sulphur vapours passed through cold water",(a)"Normal electrolyte solution"),((ii)"Soap mixed with water above critical micelle concentration",(b)"Molecular colloids"),((iii)"White of egg whipped with water",(c)"Associated colloid"),((iv)"Soap mixed with water below critical micelle concentration",(d)"Macromolecular colloids"):}
Answer» ANSWER :`(i)to(b), (ii)to (C), (iii) to (d), (IV) to (a)`

Discussion

3.	Method to distinguished RNH_(2)" and " R_(2)NH :
Answer» `NaNO_(2)//HCL` HOFFMANN's musturd OIL reaction Hinsberg test RED litmus Solution :N//A

Discussion

4.	Method of expressing concentration of solution is
Answer» MASS PERCENTAGE. VOLUME percentage. mass by volume percentage. all the above. Answer :D

Discussion

5.	Method by which lyophobic sol can be protected.
Answer» By ADDITION of oppositely charged SOL By addition of an electrolyte By addition of lyophilic sol By boiling Solution :Lyophobic sol can be protected by addition of lyophilic sol. As lyophobic sols are readily precipitated on addition of small amount of electrolytes or shaking, or HEATING HENCE they are made stable by adding lyophillic sol which STABILISES the lyophobic sols.

Discussion

6.	Method by which lyophobic sol can be protected
Answer» by ADDITION of oppositely CHARGED sol. by addition of an electrolyte by addition of lyophilic sol by BOILING Solution :Lyophilic colloids have a unique property of protecting lyophobic colloids . When a lyophilic sol is added to the lyophobic sol, the lyophilic particles form a LAYER around lyophobic particles and thus protect the latter from elctrolytes . Lysophilic colloids used fro this purpose are CALLED protective colloids.

Discussion

7.	Method by which Aniline cannot be prepared is
Answer» Hydrolysis of phenyl isocyanide with acidic solution Degradation of benzamide with bromine in alkaline solution Reduction of nitrobenzene with `H_2`/pd in ethanol Potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with AQUEOUS NAOH solution Solution :Chlorine of chlorobenzene is INERT towards NUCLEOPHILE, which is phthalimide ion

Discussion

8.	Method by which aniline can not be prepared is :
Answer» reduction of nitrobenzene with `H_(2)/Pd` in ethanol potassium SALT of phthalimide TREATED with chlorobenzene hydrolysis of phenyl ISOCYANIDE with acidic solution degradation of benzamide with bromine in ALKALINE medium solutiion. Answer :B

Discussion

9.	Methiof by which lyophobic sol can be protected.
Answer» By ADDITION of oppositely charged sol By ADDING on an ELECTROLYTE By addition of lyophilic sol By boiling Answer :C

Discussion

10.	Methanol to acetic acid
Answer» SOLUTION :`CH_3-OH+CO UNDERSET(DELTA,"PRESSURE")overset(Co(or)Rh)(rarr)CH_3-COOH`

Discussion

11.	Methanol reacts with calcium chloride to form an alcoholate of the structure :
Answer» `CaCl_(2). 2 CH_(3)OH` `CaCl_(2).4CH_(3)OH` `CaCl_(2).3CH_(3)OH` `CaCl_(2).CH_(3)OH` ANSWER :B

Discussion

12.	Methanol is used as an …………….. solvent.
Answer» SOLUTION :INDUSTRIAL

Discussion

13.	Methanol is manufactured by following process CO (g) + 2H_(2) (g) overset(ZnO//Cr_(2)O_(3))hArr CH_(3)OH (g) DeltaH^(@) = - 91 kJ Which of the following step would increase concentration of CH_(3)OH
Answer» increase in temperature ADDITION of He at constant pressure Addition of `CO (g)` Removal of catalyst Solution :(1) exothermic reaction, on increasing temperature reaction proceeds in backward direction. (2) reaction proceeds in backward direction on adding He at constant pressure ltbrrgt (3) addition of CO, INCREASES product concentration. (4) No effect on EQUILIBRIUM.

Discussion

14.	Methanol is obtained by reduction of
Answer» `CH_3-CHO` `CH_3-COOH ` `H-CONH_2 ` H-COOH ANSWER :D

Discussion

15.	Methanol is industrially prepared by
Answer» oxidation of `CH_(4)` by STEAM at `900^(@)C` REDUCTION of HCHO using `LiAlH_(4)` reaction of HCHO with a SOLUTION of NaOH reduction of CO using `H_(2)` and `ZnO - Cr_(2)O_(3)` Solution :`CO+2H_(2) overset(ZnO-Cr_(2)O_(3))to CH_(3)OH`

Discussion

16.	Methanol is acidic in nature.
Answer» SOLUTION :METHANOL is NEUTRAL in CHARACTER.

Discussion

17.	Methanol and ethanol form nearly an ideal solution at 300 K. A solution is made by mixing 32 g methanol and 23 g ethanol at 300 K. Calculate the partial pressures of its constituents and the total pressure of the solution. ["At 300 K : "P_(CH_(3)OH)="90 mm Hg,"p_(C_(2)H_(5)OH)="51 mm Hg."]
Answer» Solution :`n_(CH_(3)OH)=32//32 = "1 mol, "n_(C_(2)H_(5)OH)=23//46="0.5 mol."`

Discussion

18.	Methanol can be distinguished from ethanol by the following except:
Answer» REACTION with IODINE and alkali Reaction with salicylic acid and `H_(2)SO_(4)` Reaction with LUCAS reagent Boiling point Answer :C

Discussion

19.	Methanol and ethanol can be distiguished by the following.
Answer» By REACTION with metallic sodium By reaction with CAUSTIC soda By heating with IODINE and washing soda By heating with zinc and inorganic mineral acid Answer :C

Discussion

20.	Methanol and ethanol are two commercially important alcohols. Write one method of preparation of methanol and ethanol.
Answer» SOLUTION :`CH_3Br+NaOH(AQ)RARR CH_3OH+NaBr` `CH_2=CH_2+H_2Ooverset(H^+)rarrCH_3-CH_2OH`

Discussion

21.	Methanol and ethanol are two commercially important alcohols. The boiling point of ethanol is higher than that of methoxy methane. Give reason.
Answer» Solution :ETHANOL molecules are associated by INTERMOLECULAR hydrogen bonding. So the boiling point is HIGH. There is no hydrogen bonding in methoxymethane (ether).

Discussion

22.	Methanol and ethanol are two commercially important alcohols. Name the products obtained when ethanol is treated with CrO_3 in anhydrous medium
Answer» SOLUTION :ETHANAL or ACETALDEHYDE

Discussion

23.	Methanol and ethanol are miscible in water due to
Answer» DISSOCIATION in water their acidic NATURE hydrogen bond with water alkyl groups ANSWER :C

Discussion

24.	Methanol and ethanol are liquids of similar nature, but a mixture of them is a non-ideal solution. Why?
Answer» Solution :Both methanol and ethanol are individually associate LIQUIDS, due to intermolecular hydrogen BONDING. Upon mixing these alcohols, a homogeneous solution is FORMED. In the solution also intermolecular hydrogen BONDS are present, but compared to those present in the components is less. Hence, the mixture SHOWS positive deviation from Raoult.s law.

Discussion

25.	Methanol and ethanol are miscible in water due to :
Answer» 1. covalent character 2. hydrogen BONDING character 3. ionic bonding character 4. tendency to FORM COORDINATE bonds. Answer :B

Discussion

26.	Methanol and ethanol are distinguished by the
Answer» ACTION of HCl Iodoform test Solubility in water Sodium Solution :`C_(2)H_(5)OH` gives iodoform test having `alpha`-HYDROGEN atom while `CH_(3)OH` does not give due to the absence of `alpha`-hydrogen atom.

Discussion

27.	Methanoic acid is manufactured by the reaction of carbon monoxide and :
Answer» `NaOH` dil . HCL `PCl_(5)` conc . `H_(2)SO_(4)`. ANSWER :A

Discussion

28.	Methanoic acid reduces
Answer» Fehling.s SOLUTION `HgCl_2` Tollen.s REAGENT All ANSWER :D

Discussion

29.	Methanoic acid and inethanal can be distinguished by
Answer» Tollens reagent Sodium BICARBONATE 2, 4 D.N.P test Benedicts test Solution :Sodium bicarbonate and 2,4,-DNP test is REACT with only carbonyte compounds.

Discussion

30.	Methane reacts with oxygen at 100 atm and 300^@C in presence of Cu to give:
Answer» ACETALDEHYDE METHYL alcohol Acetic ACID ETHYL alcohol Answer :B

Discussion

31.	Methane is produced when CH_(3)MgBr reacts with
Answer» `CH_(3)CH_(2)NH_(2)` `(CH_(3)CH_(2))NH` `CH_(3)CH_(2)OH` all of these Solution :ALCOHOLS, `1^(@)` and `2^(@)` AMINES react with `CH_(3)MgBr` to EVOLVE `CH_(4)` gas.

Discussion

32.	Methane can be prepared by
Answer» WURTZ reaction Decarboxylation HYDROGENATION reaction All of these Solution :`CH_3COONa + NaOHoverset"CAO"to CH_4+Na_2CO_3`

Discussion

33.	Methanedoesnotreact withchlorideindark . Explainby givingreason .
Answer» Solution :CHLORINATIONOF methane is a FREE radical SUBSTITUTION, Toconvert `Cl_(2)`molecules intochlorine - freeradicals , energy is required whichis notavailablein dark . THUS , methanedoesnot reactwith`Cl_(2)`in dark DUE to absenceof free radicals .

Discussion

34.	Methanecannotbesynthesisedby whichof thefollowingmethods ?
Answer» WURTZ REACTION Kilbe's reaction Corey-House synthesis All of THEABOVE ANSWER :D

Discussion

35.	Methanecanbeprepared by:
Answer» wittingreaction Wurtzmethod Kolbe's method Decarboxylation ANSWER :D

Discussion

36.	Methane can beprepaedby :
Answer» ALKYL MAGNESIUM BROMIDE Wurtzreaction decarboxylation Friedel - Crafts REACTION Answer :A,C

Discussion

37.	Methane and ethane both can be obtained in single step from
Answer» `CH_3I` `C_2H_5I` `CH_3OH` `C_2H_5OH` SOLUTION :`CH_3I+2Hoverset"Zn/HCl"to CH_4+HI` `CH_3I+2Na+ICH_3underset"ETHER"OVERSET"DRY"to CH_3-CH_3-2NaI`

Discussion

38.	Methanamine reacts with a carboxylic acid derivative to form N-methylbenzamide. What kind of reaction is it called ?
Answer» ANSWER :BENZOYLATION

Discussion

39.	Methanamine to ethanamine
Answer» SOLUTION :`underset(("Ethana MINE"))(CH_(3)-CH_(2)-NH_(2)) underset(H_(2)O)overset(HNO_(2))RARR CH_(3)CH_(2)OHoverset((O))rarr CH_(3)COOH overset(NH_(3))rarr CH_(3)COONH_(4) overset(Delta)rarr CH_(3)CONH_(2) overset(Br_(2)//KOH)rarr underset(("METHANAMINE"))(CH_(3)NH_(2))`

Discussion

40.	Methanal is a highly pungent gas at room temperature
Answer» ANSWER :T

Discussion

41.	Methanal is
Answer» `CH_(3)CHO` `CH_(3)COCH_(3)` `CH_(2)OH` `HCHO` SOLUTION :`CH_(3)CHO to`METHANAL.

Discussion

42.	Methanal (HCHO) is an aldehyde having no alpha hydrogen atom. What are the products formed when methanal is treated with strong KOH solution?
Answer» ANSWER :METHANOL and POTASSIUM methanoate `2HCHO+KOH RARR CH_3OH+HCOOK`

Discussion

43.	Methanal, ethanal and propanone are miscible withwater in all proportions. What is this due to ?
Answer» SOLUTION :HYDROGEN BONDING

Discussion

44.	Metch the properties given in column I with the metals given in column II
Answer» `i-c,ii-d,iii-e,iv-a` `i-c,ii-d,iii-b,iv-a` `i-c,ii-d,iii-a,iv-e` `i-d,ii-c,iii-a,iv-e` SOLUTION :N//A

Discussion

45.	Metaphosphoric acid is:
Answer» `H_3PO_2` `HPO_3` `H_3PO_3` `H_3PO_4` ANSWER :B

Discussion

46.	Metamers of ethyl propionate are:
Answer» `C_(4)H_(9)COOH` and `HCOOC_(4)H_(7)` `CH_(4)H_(9)COOH` and `CH_(3)COOC_(3)H_(7)` `CH_(3)COOCH_(3)` and `CH_(3)COOC_(3)H_(7)` `CH_(3)COOC_(3)H_(7)` and `C_(3)H_(7)COOCH_(3)` Answer :D

Discussion

47.	Metamers can also be chain or position isomers. (R) The term tautomerism was introduced to explain the reactivity of a substance according to two possible structures.
Answer» ANSWER :B

Discussion

48.	Metamerism is present in
Answer» `CH_(3) - O -CH_(3)` `CH_(3)-CO-CH_(3)` `CH_(3)-CO-C_(2)H_(5)` `CH_(3)-CO-C_(3)H_(7)` ANSWER :D

Discussion

49.	Metamerism is shown by:
Answer» Ethyl ALCOHOL and dimethyl ether Acetone and propionaldehyde Propionic acid and ACETIC acid Methyl n-propyl ether and DIETHYL ether Answer :D

Discussion

50.	Metamerism is possible in
Answer» same POLYVALENT FUNCTIONAL group same MONOVALENT functional group different polyvalent functional group different monovalent functional group Answer :A

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Pb and Sn are exerted from their chief ores by:

Method to distinguished RNH_(2)" and " R_(2)NH :

Method of expressing concentration of solution is

Method by which lyophobic sol can be protected.

Method by which lyophobic sol can be protected

Method by which Aniline cannot be prepared is

Method by which aniline can not be prepared is :

Methiof by which lyophobic sol can be protected.

Methanol to acetic acid

Methanol reacts with calcium chloride to form an alcoholate of the structure :

Methanol is used as an …………….. solvent.

Methanol is manufactured by following process CO (g) + 2H_(2) (g) overset(ZnO//Cr_(2)O_(3))hArr CH_(3)OH (g) DeltaH^(@) = - 91 kJ Which of the following step would increase concentration of CH_(3)OH

Methanol is obtained by reduction of

Methanol is industrially prepared by

Methanol is acidic in nature.

Methanol and ethanol form nearly an ideal solution at 300 K. A solution is made by mixing 32 g methanol and 23 g ethanol at 300 K. Calculate the partial pressures of its constituents and the total pressure of the solution. ["At 300 K : "P_(CH_(3)OH)="90 mm Hg,"p_(C_(2)H_(5)OH)="51 mm Hg."]

Methanol can be distinguished from ethanol by the following except:

Methanol and ethanol can be distiguished by the following.

Methanol and ethanol are two commercially important alcohols. Write one method of preparation of methanol and ethanol.

Methanol and ethanol are two commercially important alcohols. The boiling point of ethanol is higher than that of methoxy methane. Give reason.

Methanol and ethanol are two commercially important alcohols. Name the products obtained when ethanol is treated with CrO_3 in anhydrous medium

Methanol and ethanol are miscible in water due to

Methanol and ethanol are liquids of similar nature, but a mixture of them is a non-ideal solution. Why?

Methanol and ethanol are miscible in water due to :

Methanol and ethanol are distinguished by the

Methanoic acid is manufactured by the reaction of carbon monoxide and :

Methanoic acid reduces

Methanoic acid and inethanal can be distinguished by

Methane reacts with oxygen at 100 atm and 300^@C in presence of Cu to give:

Methane is produced when CH_(3)MgBr reacts with

Methane can be prepared by

Methanedoesnotreact withchlorideindark . Explainby givingreason .

Methanecannotbesynthesisedby whichof thefollowingmethods ?

Methanecanbeprepared by:

Methane can beprepaedby :

Methane and ethane both can be obtained in single step from

Methanamine reacts with a carboxylic acid derivative to form N-methylbenzamide. What kind of reaction is it called ?

Methanamine to ethanamine

Methanal is a highly pungent gas at room temperature

Methanal is

Methanal (HCHO) is an aldehyde having no alpha hydrogen atom. What are the products formed when methanal is treated with strong KOH solution?

Methanal, ethanal and propanone are miscible withwater in all proportions. What is this due to ?

Metch the properties given in column I with the metals given in column II

Metaphosphoric acid is:

Metamers of ethyl propionate are:

Metamers can also be chain or position isomers. (R) The term tautomerism was introduced to explain the reactivity of a substance according to two possible structures.

Metamerism is present in

Metamerism is shown by:

Metamerism is possible in