Why is bromination more selective than chlorination?
Bromination of alkanes occurs by a similar mechanism, but is slower and more selective because a bromine atom is a less reactive hydrogen abstraction agent than a chlorine atom, as reflected by the higher bond energy of H-Cl than H-Br.
Which is more selective chlorination or bromination?
Reason: Bromination of alkane is highly selective compared to chlorination reaction.
Is bromination more stable than chlorination?
Why: Chlorine is more reactive the bromine because chlorine radical is less stable then bromine radical.
Which is faster bromination or chlorination?
Chlorination is faster than bromination because chlorine is more reactive.
Why chlorination is more reactive and less selective?
Chlorination is less selective than bromination because chlorination has smaller differences in activation energy for attack at 1°, 2°, and 3° positions. Consider the halogenation of propane at the 1° and 2° positions. Formation of the different halopropanes occurs during the chain propagation steps.
What is the selectivity ratio of chlorine?
This gives us a ratio of 55:15 , or 3.66. So for this reaction, the free radical chlorination of propane at 25°C, chlorine is 3.66 times more selective for secondary hydrogens than for primary hydrogens.
Which element is most selective in its halogenation?
The nature of the substrate determines the pathway. The facility of halogenation is influenced by the halogen. Fluorine and chlorine are more electrophilic and are more aggressive halogenating agents. Bromine is a weaker halogenating agent than both fluorine and chlorine, while iodine is the least reactive of them all.
Why does bromine react faster than chlorine?
Because a bromine atom has one more full shell than a chlorine atom, it has more shielding which means the attraction between the nucleus and an electron is weaker.
Why is chlorine not selective?
Since chlorine is a rather reactive reagent, it shows relative low selectivity, that means Cl2 does not discriminate greatly among the different types of hydrogens atoms (primary, secondary or tertiary) in an alkane.
Where is bromination most likely to occur?
Well as an example of the conclusions we could make: Bromination is 1640 times more likely to occur at a 3o position than 1. Chlorination is 5.2 times more likely to occur at a 3o position than 1….
| Br | Cl | |
|---|---|---|
| 1o | 1 | 1 |
| 2o | 82 | 3.9 |
| 3o | 1640 | 5.2 |
Is radical chlorination less selective?
Sulfuryl chloride (SO2Cl2) can also be used as a chlorinating agent and reacts with alkyl radicals in a chain reaction. The SO2Cl radical is less reactive than the Cl radical and is therefore more selective.
Which halogen is the most selective in a radical halogenation?
The fluorine radical is the most reactive of the halogen radicals, and it reacts violently with alkanes.