JEE Main Previous Year Papers Questions With Solutions Chemistry Nitro,Amine and Azo Compounds

JEE Main Previous Year Papers Questions With Solutions Chemistry Nitro, Amine and Azo Compounds

1.When primary amine reacts with chloroform in etharioicKOH then the product is (2002)
1) an isocyanide                    2) an aldehyde
3) a cyanide                           4) an alcohol
Ans.

2.The reaction of chloroform with alcoholic KOH and p-toludine forms   (2003)

Ans.

3.The correct order of increasing basic nature for the bases NH₃. CH₃NH₂ and (CH₃)₂NH is(2003)
1)(CH₃ )₂ NH < NH₃ < CH₃NH₂
2)NH₃ < CH,NH₂ < (CH3 )₂ NH
3)CH₃NH₂ < (CH₃ )₂ NH < NH₃
4)CH₃NH₂ < NH₃ < (CH₃)₂ NH
Ans.(2) More is the no. of +1 groups attached to N atom greater is the basic character.

4.Ethyl isocyanide on hydrolysis in acidic medium generates  (2003)
1)propanoic acid and ammonium salt .
2)ethanoic acid and ammonium salt
3)methylamine salt and ethanoic acid
4)ethylamine salt and methanoic acid
Ans.

5.The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5M sodium hydroxide solution hydroxide solutio for complete neutralization. The organic compound is 1)acetamide           2) thiourea            (2004)
3) urea                       4) benzamide
Ans.(3) Urea has C and N atoms in the ratio 1:2.

6.Which of the following is the strongest base?

Ans.(2)1° aliphalic amine.

7.Which one of the following methods is neither meant for the synthesis nor for separation of amines ? (2005)
1) Hinsberg method 2) Hofmann method 3) Wurtz reaction 4) Curtius reaction
Ans.(3) Alkanes are obtained in Wurtz reaction.

8.Amongst the following the most basic compound is   (2005)
1) benzylamine                    2)    aniline
3) acetanilide                       4)    p-nitroaniline
Ans.(1) -NH₂ group is not linked with benzene ring

9.An organic compound having molecular mass 60 is found to contain C=20%, H=6.67% and N=46.67% while rest is oxygen. On heating it gives NH₃ alongwith a solid residue. The solid residue give violet colour with alkaline copper sulphate solution. The compound is (2005)
1) CH₃NCO           2)  CH_{3 CONH2}
3) (NH₂)₂CO         4)    CH₃CH₂CONH₂
Ans. (3)Emperical formula CH₄ON₂.

10.Fluorobenzene (C₆H₅F) can be synthesized in the laboratory (2006)
1)by heating phenol with HF and KF
2)from aniline by diazotisation followed by heating the diazonium salt with HBF₄
3)by direct fluorination of benzene with F₂ gas
4)by reacting bromobenzene with NaF solution
Ans.(2) Fluordrenzene is syntherised fro C₆H₅HBF₄

11. CH₃CH₂NH₂+CHa₃+3KOH –>(A)+(B) + 3H20 In the chemical reaction, the compound (A) and (B) are respectively       (2007)
1)C₂H₅CN and 3KCl
2)CH₃CH₂CONH₂ and 3KCl
3)C₂H₅NC and K₂ C0₃
4)C₂H₅NC and 3KCl
Ans.(4) It is example of carbylamine reaction. The product will be C₂H₅

12.Which one of the following is the strongest base in aqueous solution ? (2007)
1) Trimethylamine            2) Aniline
3) Dimethylamine              4) Methylamine
Ans.(3) In aqueous solution basicity order of 1°, 2° and 3° amine with methyl group is 2° > 1° > 3°.In case of aniline lone pair of nitrogen is involved in resonance, so it is weaker base than aliphatic amines.

13.Toluene is nitrated and the resulting product ‘ is reduced with tin and hydrochloric acid. The product so obtained is diazotised and then heated with cuprotis bromide. The reaction mixture so formed contains (2008)
1)mixture of o – and p-bromotoluences
2)mixture of o- and p-dibromobenzenes
3)mixture of o- and p-bromoanilines
4)mixture of o-and m-bromotoluenes
Ans.

14.In the chemical reactions, the compound ‘A’ and ‘B’ respectively are    (2010)

Ans.

15.A compound with molecular mass 180 is acylated with CH₃COC/ to get a compound * with molecular mass 390. The number of amino groups present per molecule of the former compound is  (2013)
1) 2                 2) 5                  3) 4                  4)6
Ans.

16.On heating an aliphatic primary amine with chloroform and ethanolic potassium hydroxide, the organic compound formed is            (2014)
1) an alkyl isocyanide            2) an alkanol
3) an alkanediol                   4) an alkyl cyanide
Ans.(1) R – NH₂ + CHC1₃ + KOH -> R – NC Alkylisocyanide is obtained.

17.Considering the basic strength of amines in aqueous solution, which one has the smallest pK_b vale ?(2014)
1)C₆H₅NH_{2       2) (CH3)2NH}
3) CH₃NH_{2     4) (CH3)3N}
Ans.(2) (CH₃)₂NH is a stronger base in aqueous medium than Me₃ So its pK_b value is smallest.

Ans.(3) Sandmayer reaction.