Organic Reactions

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15 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

Which of the following statements is/are true?
A. Benzene reacts with isobutyl chloride in presence of anhydrous AlCl3 to give isobutyl benzene.
B. Bayer’s reagent can be used to distinguish cyclopropane from propene.
C. Ethyne and its derivatives give white precipitate with ammoniacal silver nitrate solution.

  1. Only A
  2. Only B
  3. Only C
  4. Both A and B
  5. Both B and C
Question 2 Multiple Choice (Single Answer)

Assertion: Reaction of 1, 3-dibromopropane with zinc produces cyclopropane.
Reason: The reaction of alkyl halides with zinc dust is called Frankland reaction.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 3 Multiple Choice (Single Answer)

Assertion: Fredel-Crafts reaction of benzene with n-propyl chloride gives isopropylbenzene.
Reason: Benzene undergoes electrophilic substitution readily.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 4 Multiple Choice (Single Answer)

Assertion: Benzene reacts with Cl2 in presence of light to form BHC.
Reason: BHC is also called gammexane or 666.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 5 Multiple Choice (Single Answer)

Assertion: Addition of HI to vinyl chloride produces 1-chloro-1-iodoethene.
Reason: HI adds to vinyl chloride against Markownikov’s rule.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 6 Multiple Choice (Single Answer)

Assertion: Propene is more reactive than ethene towards electrophilic addition reactions.
Reason: Hyperconjugation effect of the CH3 group increases the electron density in the double bond.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 7 Multiple Choice (Single Answer)

Assertion: Addition of Br2 to maleic acid gives (+) and (-) forms of the product.
Reason: Addition of Br2 to maleic acid follows trans-addition.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 8 Multiple Choice (Single Answer)

Assertion: Both cyclopropane and propene give addition reactions readily.
Reason: Cyclopropane and propene are isomers of each other.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 9 Multiple Choice (Single Answer)

Assertion: Propene reacts with perbenzoic acid to produce 1, 2-epoxypropane.
Reason: In this reaction, propene acts as a nucleophile.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 10 Multiple Choice (Single Answer)

Assertion: 2, 3-Dimethylbut-2-ene is more stable than but-2-ene.
Reason: Twelve hyperconjugation structures can be written for 2, 3-Dimethylbut-2-ene while but-2-ene has only six.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 11 Multiple Choice (Single Answer)

Assertion: Acetylene reacts with sodamide to evolve H2 gas.
Reason: Acetylene is a weaker acid than ammonia.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 12 Multiple Choice (Single Answer)

Assertion: Acidity of the C-H bond decreases in the order; HC≡CH > H2C=CH2 > H3C−CH3.
Reason: Acidity of the C-H bond increases as the electronegativity of the carbon to which it is attached increases.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 13 Multiple Choice (Single Answer)

Assertion: Addition of H2O to acetylene occurs in presence of dil. H2SO4 and HgSO4 to give acetaldehyde.
Reason: It is an example of electrophilic addition reaction.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 14 Multiple Choice (Single Answer)

Assertion: But-1-yne reacts with Tollen’s reagent to give white precipitate of silver but-1-ynide, but but-2-yne does not react.
Reason: But-1-yne has acidic hydrogen but but-2-yne does not.

  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
  5. Both A and R are false.
Question 15 Multiple Choice (Single Answer)

Which of the following statements is/are false?

  1. Lindlar’s catalyst is palladium supported over calcium carbonate, but partially poisoned by addition of lead acetate.
  2. –COOCH3 is a meta-directing group while OCOCH3 is an ortho-, para- directing group.
  3. Both 1 and 2
  4. When acetylene reacts with methyl magnesium bromide, hydrogen is evolved.
  5. None of these