The key difference between nitrobenzene and aniline is that nitrobenzene has a nitro group attached to the benzene ring, whereas aniline has an amine group attached to the benzene ring.
The two compounds nitrobenzene and aniline differ from each other according to the substituent chemical group on their benzene ring.
CONTENTS
1. Overview and Key Difference
2. What is Nitrobenzene
3. What is Aniline
4. Nitrobenzene vs Aniline in Tabular Form
5. Summary – Nitrobenzene vs Aniline
What is Nitrobenzene?
Nitrobenzene is an organic compound having the chemical formula C6H5NO2. It is a water-insoluble oil with a pale yellow appearance and an almond-like odor. Moreover, it can freeze, giving greenish-yellow crystals. Nitrobenzene is produced on a large scale from benzene.
Figure 01: The Chemical Structure of Nitrobenzene
In the production process of nitrobenzene, it uses the nitration of benzene with a mixture of concentrated sulfuric acid, water, and nitric acid. Sometimes, this mixture is named a mixed acid. This is one of the most dangerous methods because it is a highly exothermic reaction. The molar mass of nitrobenzene is 123.11 g/mol. It appears as a yellowish, oily liquid with a pungent odor. The density of this liquid is 1.199 g/cm3. The melting point of nitrobenzene is 5.7 degrees Celsius while the boiling point is 210.9 degrees Celsius. It has poor solubility in water.
When considering the uses of nitrobenzene, most of it is converted into aniline via hydrogenation. Aniline is useful as a precursor to urethane polymers, rubber chemicals, pesticides, dyes, explosives, and pharmaceuticals. Moreover, this compound is selectively reduced to azoxybenzene, azobenzene, nitrosobenzene, hydrazobenzene, etc.
What is Aniline?
Aniline is an aromatic organic compound having the chemical formula C6H5NH2. It has a benzene ring (a phenyl group) attached to an amine group (-NH2). It is the simplest aromatic amine because there are no components other than the amine group and the aromatic ring. This compound is also slightly pyramidalized and is flatter than an aliphatic amine. Its molar mass is 93.13 g/mol. Furthermore, its melting point is −6.3 °C, while the boiling point is 184.13 °C. It has the odour of rotten fish.
Industrially, we can produce this compound via two steps. The first step is the nitration of benzene with a concentrated mixture of nitric acid and sulfuric acid (at 50 to 60 °C). This gives nitrobenzene. Then we can hydrogenate nitrobenzene into aniline in the presence of a metal catalyst. The reaction is as follows:
Figure 02: Aniline from Nitrobenzene
Moreover, this compound is mainly used in the manufacture of polyurethane precursors. Apart from that, we can use this compound in the production of dyes, drugs, explosive materials, plastics, photographic and rubbery chemicals, etc.
What is the Difference Between Nitrobenzene and Aniline?
Nitrobenzene and aniline are important organic compounds that are aromatic. The key difference between nitrobenzene and aniline is that nitrobenzene has a nitro group attached to the benzene ring, whereas aniline has an amine group attached to the benzene ring. Moreover, nitrobenzene is a pale yellow to dark brown liquid, while aniline is an oily liquid that is colorless to brown. In addition, nitrobenzene is used to produce aniline whereas aniline is useful as a precursor to urethane polymers, rubber chemicals, pesticides, dyes, explosives, and pharmaceuticals.
The below infographic presents the differences between nitrobenzene and aniline in tabular form for side-by-side comparison.
Summary – Nitrobenzene vs Aniline
Nitrobenzene is an organic compound having the chemical formula C6H5NO2. Aniline is an aromatic organic compound having the chemical formula C6H5NH2. The key difference between nitrobenzene and aniline is that nitrobenzene has a nitro group attached to the benzene ring, whereas aniline has an amine group attached to the benzene ring.
Reference:
1. “Aniline.” Wikipedia, Wikimedia Foundation.
Image Courtesy:
1. “Nitrobenzol” By NEUROtiker – Own work (Public Domain) via Commons Wikimedia
2. “Aniline from Nitrobenzene” By Hermann Luyken – Own work (CC0) via Commons Wikimedia