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What happens when benzene undergoes nitration?
Nitration happens when one (or more) of the hydrogen atoms on the benzene ring is replaced by a nitro group, NO2. Benzene is treated with a mixture of concentrated nitric acid and concentrated sulphuric acid at a temperature not exceeding 50°C. Nitro groups “direct” new groups into the 3 and 5 positions.
What is the product of nitration of benzene?
Nitration and sulfonation of benzene are two examples of electrophilic aromatic substitution. The nitronium ion (NO2+) and sulfur trioxide (SO3) are the electrophiles and individually react with benzene to give nitrobenzene and benzenesulfonic acid respectively.
What happens when benzene reacts with conc hno3in the presence of conc h2so4 at 600?
When benzene is heated with concentrated sulfuric acid ( H2SO4) and concentrated nitric (HNO3) acid, nitrobenzene is given as the product. A hydrogen atom of benzene is replaced by a nitro group (-NO2) in this reaction.
What type of reaction are shown by benzene?
Substitution Reactions of Benzene and Other Aromatic Compounds
| Reaction Type | Typical Equation | |
|---|---|---|
| Halogenation: | C6H6 | + Cl2 & heat FeCl3 catalyst |
| Nitration: | C6H6 | + HNO3 & heat H2SO4 catalyst |
| Sulfonation: | C6H6 | + H2SO4 + SO3 & heat |
| Alkylation: Friedel-Crafts | C6H6 | + R-Cl & heat AlCl3 catalyst |
Which electrophile is formed during nitration of benzene?
nitronium ion
The formation of the electrophile The electrophile is the “nitronium ion” or the “nitryl cation”, NO+2. This is formed by reaction between the nitric acid and the sulphuric acid.
What characteristic reactions of benzene occur when a nitro (- NO2 group replaces one of the hydrogens atoms bonded to the ring?
The nitration of benzene Nitration happens when one (or more) of the hydrogen atoms on the benzene ring is replaced by a nitro group, NO2. Benzene is treated with a mixture of concentrated nitric acid and concentrated sulfuric acid at a temperature not exceeding 50°C.
What are nitro Arenes?
The nitroarenes are a large class of structurally related chemicals nor- mally found in particulate emissions from many combustion sources, most notably, diesel exhausts. These molecules are nitro-substituted. derivatives of polycyclic aromatic hydrocarbons (arenes) with at least.
Which Electrophile is formed during nitration of benzene?
What happens when benzene is treated with conc h2so4and conc hno3 at 330 K?
Explanation: Benzene when treated with concentrated nitric acid and sulfuric acid at 330K temperature it forms nitrobenzene that is nitration occurs. The reaction is highly explosive and risky as a lot of heat is evolved during the reaction.
What happens when benzene is heated with conc h2so4?
Heating benzene with conc. sulphuric acid for a few hours results in the formation of benzenesulphonic acid. This reaction is an electrophilic substitution reaction.
Which is the nitro group in the nitration of benzene?
The nitration of benzene is another example of an electrophilic aromatic substitution reaction. In this reaction, a hydrogen atom on the benzene ring is substituted with a nitro group (-NO 2 ).
How does the nitronium ion react with benzene?
This leads to the cleavage of the bond between the nitrogen and the protonated oxygen, with the electrons going onto the oxygen (neutralizing the charge), and releasing water. This forms the electrophilic nitronium ion required for reaction with benzene: With the nitronium ion electrophile formed, it can react with the benzene ring.
Which is a better electrophile nitric acid or benzene?
As with other electrophilic aromatic substitution reactions, the benzene ring acts as a nucleophile. However, nitric acid (HNO 3) is not a very good electrophile (nor is benzene a very good nucleophile). Sulfuric acid (H 2 SO 4) helps overcome this by converting nitric acid into nitronium ions (NO 2+ ), which are much better electrophiles.
How does Nitro break the C-H bond in benzene?
This is accomplished by removing the hydrogen atom on the benzene carbon bonded to the new nitro group. The water molecule released earlier can act as a base, donating a lone pair to this hydrogen, breaking the C-H bond, and re-forming the double bond in the benzene ring (or more accurately, re-establishing the aromaticity of the benzene ring).