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Which of the following statem ents regarding free radical halogenation o f alkane is not true?
- a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination
- b)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in bromination
- c)A single halogen radical may bring about halogenation of thousands of alkane molecules
- d)Continuous source of energy is required to continue the free radical halogenation reaction
Correct answer is option 'A'. Can you explain this answer?
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Which of the following statem ents regarding free radical halogenation...
Hydrogen abstraction by halogen radical in the propagation step is exothermic in chlorination but endothermic in bromination. Hence, the option (A) is an incorrect statement.
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Which of the following statem ents regarding free radical halogenation...
Hydrogen abstraction by halogen radical in the propagation step is exothermic in chlorination but endothermic in bromination.
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Which of the following statem ents regarding free radical halogenation...
Statement: Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination.
Explanation:
In free radical halogenation of alkanes, the reaction proceeds through a chain reaction mechanism consisting of three steps: initiation, propagation, and termination.
1. Initiation:
- In this step, a small amount of energy (such as heat or light) is supplied to break the halogen molecule (X2) into two halogen radicals (X·).
- This is an endothermic process as energy is required to break the bond.
2. Propagation:
- In the propagation step, the halogen radical (X·) abstracts a hydrogen atom from the alkane molecule (RH), forming a hydrogen halide (HX) and an alkyl radical (R·).
- This step is exothermic because the bond energy of the hydrogen-halogen bond is lower than the bond energy of the hydrogen-carbon bond.
- The formation of a more stable hydrogen halide and the release of energy contribute to the exothermic nature of the propagation step.
3. Termination:
- In the termination step, two radicals (either alkyl radicals or halogen radicals) combine to form a non-radical product, effectively terminating the chain reaction.
- This step is exothermic because the bond energy of the new non-radical product is generally higher than the bond energy of the radicals.
Analysis of the Incorrect Statement:
The incorrect statement is option 'A', which states that hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination.
- In chlorination, the hydrogen abstraction by chlorine radical (Cl·) is indeed exothermic in the propagation step, as explained above.
- However, in bromination, the hydrogen abstraction by bromine radical (Br·) is also exothermic in the propagation step. This is because the bond energy of hydrogen-bromine bond is lower than the bond energy of the hydrogen-carbon bond, leading to the release of energy.
Therefore, the incorrect statement is option 'A' because hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination.
Explanation:
In free radical halogenation of alkanes, the reaction proceeds through a chain reaction mechanism consisting of three steps: initiation, propagation, and termination.
1. Initiation:
- In this step, a small amount of energy (such as heat or light) is supplied to break the halogen molecule (X2) into two halogen radicals (X·).
- This is an endothermic process as energy is required to break the bond.
2. Propagation:
- In the propagation step, the halogen radical (X·) abstracts a hydrogen atom from the alkane molecule (RH), forming a hydrogen halide (HX) and an alkyl radical (R·).
- This step is exothermic because the bond energy of the hydrogen-halogen bond is lower than the bond energy of the hydrogen-carbon bond.
- The formation of a more stable hydrogen halide and the release of energy contribute to the exothermic nature of the propagation step.
3. Termination:
- In the termination step, two radicals (either alkyl radicals or halogen radicals) combine to form a non-radical product, effectively terminating the chain reaction.
- This step is exothermic because the bond energy of the new non-radical product is generally higher than the bond energy of the radicals.
Analysis of the Incorrect Statement:
The incorrect statement is option 'A', which states that hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination.
- In chlorination, the hydrogen abstraction by chlorine radical (Cl·) is indeed exothermic in the propagation step, as explained above.
- However, in bromination, the hydrogen abstraction by bromine radical (Br·) is also exothermic in the propagation step. This is because the bond energy of hydrogen-bromine bond is lower than the bond energy of the hydrogen-carbon bond, leading to the release of energy.
Therefore, the incorrect statement is option 'A' because hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and bromination.
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Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer?
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Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? for Class 11 2024 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 11 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer?.
Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? for Class 11 2024 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 11 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer?.
Solutions for Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 11.
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Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Which of the following statem ents regarding free radical halogenation o f alkane is not true?a)Hydrogen abstraction by halogen radical in the propagation step is exothermic in both chlorination and brominationb)Hydrogen abstraction by halogen radical in propagation step is exothermic in chlorination but endothermic in brominationc)A single halogen radical may bring about halogenation of thousands of alkane moleculesd)Continuous source of energy is required to continue the free radical halogenation reactionCorrect answer is option 'A'. Can you explain this answer? tests, examples and also practice Class 11 tests.
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