Question 1:

Compare the torsional strain in the gauche conformer of butane with the anti-conformer.

Draw Newman projections of both and indicate the values of the dihedral angles between Me’s.

 

Question 2:

Prepare

(1) Butane from chloroethane using the Corey – House synthesis.

(2) Deuteropropane from isopropyl bromide

 

Question 3:

The compound with highest boiling point is

1) n-hexane

2) n-pentane

3) 2,2-dimethyl propane

4) 2-methylbutane

 

Question 4:

The order of reactivity of halogens towards halogenation of alkanes is

1) F₂ > Br₂ > Cl₂

2) F₂ > Cl₂ > Br₂

3) Cl₂ > F₂ > Br₂

4) Cl₂ > Br₂ > F₂

 

Question 5:

Why do the C – C bond breaks rather than C – H bonds during cracking of alkanes?

 

Question 6:

The number of sigma & pi bonds in 1-butene-3-yne are

a) 5 sigma; 5 pi

b) 7 sigma; 3 pi

c) 8 sigma; 2 pi

d) 6 sigma; 4 pi

 

    Question 7:

      

Correct statements are

1) I is racemic mixture by anti-addition

2) II is meso compound by anti-addition

3) I is meso compound by syn-addition

4) II is racemic compound by syn-addition

 

   Question 8:

                                                                 

Which statement is true about this reaction?

1) A is meso 1,2-butan-di-ol formed by syn-addition

2) A is meso 1,2-butan-di-ol formed by anti-addition

3) A is racemic mixture of d & l, 1,2-butan-di-ol formed by anti-addition.

4) A is racemic mixture of d & l, 1,2-butan-di-ol formed by syn-addition.

 

Question 9:

A compound on reductive ozonolysis produces two moles of formaldehyde and one mole of glyoxal. The compound is

1) But-2-ene

2) 1,3-butadiene

3) 1,3-pentadiene

4) 1,4-pentadiene

 

Question 10:

How alkene can be obtained from vicinal dihalides?

 

Question 11:

Ethane can be separated from Ethyne by passing the mixture through

1) Conc. H₂SO₄

2) Ammonical Cu₂Cl₂

3) Pyrogallol

4) Charcoal powder

 

Question 12:

How is ethyne prepared on industrial scale from Calcium carbide?

 

Question 13:

How will you prepare propanone from propyne?        

 

Question 14:

Write the reaction of cyclic polymerisation of Ethyne to benzene.

 

Question 15:

How is ethyne prepared from 1,2-Dibromoethane?

 

Question 16:

Give reaction for preparation of Benzene from Na salt of benzoic acid.

 

Question 17:

What happens when benzene is heated in air?

 

Question 18:

Give Friedel craft’s alkylation reaction of benzene to produce toluene?

 

Question 19:

Give Friedel craft’s acylation reaction of benzene to produce Acetophenone by using acetic anhydride?

 

Question 20:

Give the reaction for preparation of benzene from phenol.

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