Which of the following Halogens react fast with alkanes in substitution reactions?
Correct answer: B. F2
- A. Cl2
- B. F2
- C. I2
- D. Br2
Explanation
Fluorine (F) is the most reactive halogen and therefore reacts faster with alkanes in substitution reactions. This is because fluorine has the smallest atomic radius and highest electronegativity of all the halogens, making it highly reactive and able to break the strong carbon-hydrogen bonds in alkanes. F2 > Cl2 > Br2 > I2 The reactivity of halogen decreases in this order. Hence this is the only correct option.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Free Radical Substitution
Free radical substitution explains how alkanes react with halogens under ultraviolet light or heat through initiation, propagation and termination steps. The mechanism involves homolytic bond fission and radical intermediates, while product formation depends on the relative stability of radicals and differs from ionic substitution.
Practise Chemistry of Hydrocarbons
1,093 free Chemistry of Hydrocarbons MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Free Radical Substitution questions
Which of the following gives a free radical reaction when reacting with alkanes?
Free radical reactions take place in the presence of _?
Which of the following are products of the following reaction in the presence of sunlight? CH4+Cl2→ ?
Free radical reactions take place in the presence of _.
Which of the following gives a free radical reaction when it reacts with alkanes?
In the following, which one is a free radical?