Table of Contents
- 1 Why direct fluorination and iodination reaction of alkanes are not possible?
- 2 Why is free radical iodination of alkanes usually impossible?
- 3 Why is free radical substitution generally not suitable for laboratory preparation of Haloalkanes?
- 4 Why does free radical halogenation usually give mixtures of products?
- 5 Why alkyl halides are not prepared in the lab by free radical halogenation of alkanes give one reason?
- 6 Why is the reaction between alkanes and fluorine difficult to control?
- 7 How do you prepare fluoromethane from radical fluorination?
Why direct fluorination and iodination reaction of alkanes are not possible?
Why is the direct fluorination and iodination of alkanes via a free radical mechanism not possible? – Quora. Fluorination of alkanes is highly exothermic which may explode. Iodination of alkanes is reversible reaction,as HI so produced is stronger reducing agent,it attacks on Alkyl iodides produced.
Why is free radical iodination of alkanes usually impossible?
Free-radical iodination is usually not possible because iodine is too unreactive to form a radical.
Why is the free radical reaction not the most preferred way to prepare alkyl halides?
Free radical halogenation is not suitable method for laboratory preparation of alkyl halides because of the following reasons : (i) Because of the presence of different types of hydrogen atoms present in alkanes they give a mixture of isomeric monohalogenated products whose boiling points are so close that they cannot …
Why direct iodination is not possible?
Explanation: However, direct iodination of benzene in this manner is not possible. This is because iodination of benzene in this manner produces HI as a side product. HI being a strong reducing agent, reduces the halobenzene back to benzene, and thus the reaction becomes reversible in nature.
Why is free radical substitution generally not suitable for laboratory preparation of Haloalkanes?
Free radical substitution is generally not suitable for laboratory preparation of haloalkanes. Because a mixture of isomers are formed which are difficult to separate.
Why does free radical halogenation usually give mixtures of products?
Explain why free-radical halogenation usually gives mixtures of products. Free-radical halogenation substitutes a halogen atom for a hydrogen atom. The first substitution of a hydrogen atom will produce a different compound. The remaining hydrogen atoms can now compete for available halogen atoms.
Why is iodination and fluorination of benzene difficult?
Fluorine is most electrophilic, and Iodine is least. Therefore, Fluorination is highly reactive, and Iodination is highly unreactive for electrophilic aromatic substitution reactions. The exothermic rates of aromatic halogenation also decrease from Fluorine to Iodine.
Why direct iodination of benzene is not possible because?
Direct iodination of benzene is not possible because the reaction is reversible and the HI so produced in the reaction is a very strong reducing agent which reduces iodobenzene back to benzene.
Why alkyl halides are not prepared in the lab by free radical halogenation of alkanes give one reason?
‘Alkyl halides’ are generally not prepared in laboratories by ‘free radical halogenation’ of alkanes because, the presence of different types of hydrogen atoms in alkanes. EXPLANATION: These hydrogen atoms make it difficult to break the bond and separate the alkanes in laboratories.
Why is the reaction between alkanes and fluorine difficult to control?
The reaction of alkanes with fluorine is difficult to control because the activation energy for hydrogen abstraction is so low. The initiation step involves the homolytic cleavage of the F-F bond. F-F → F· + ·F; E_a = + 155 kJ/mol This is a high activation energy. But only a few F atoms need to form.
Why is the iodination of alkanes a reversible reaction?
Iodination of alkanes is reversible reaction,as HI so produced is stronger reducing agent,it attacks on Alkyl iodides produced.Hence backward reaction is attributed. In order to prevent backward reaction, iodination of alkanes is carried in presence of oxidising agents like HgO or HIO3 or HIO3.
Why is iodination of alkanes carried in presence of oxidising agents?
In order to prevent backward reaction, iodination of alkanes is carried in presence of oxidising agents like HgO or HIO3 or HIO3. Direct fluorination is extremely exothermic and can it the F radical are extremely reactive. They form a large number of products in gaseous state that are very difficult to seperate.
How do you prepare fluoromethane from radical fluorination?
Radical Fluorination is a very exothermic and violent reaction. Because of this, radical fluorination is avoided in the laboratory. Instead, we use Swart’s reaction, a type of halide exchange reaction. Here, we prepare Chloromethane by radical chlorination of methane, and then react it with Silver fluoride to get Fluoromethane