Chemical distinction between ethylamine and aniline

In the chemical industry, it is crucial to distinguish between different chemical substances. Ethylamine and aniline are both amine compounds, but they have significant differences in structure and properties. This article will analyze in detail how to distinguish these two substances by chemical methods.

Analysis of Basic Properties of 1.

1. Physical Properties

• solubility: Ethylamine is slightly soluble in water, while aniline is less soluble and usually exists in solid form.
• Density: Ethylamine has a density of about 0.74g/cm³, while aniline has a density of about 1.02g/cm³.
• Smell ethylamine has a strong pungent odor, while aniline has a more elegant odor.

1. Structural differences

• the chemical structure of ethylamine is CH3CH2CONH2, while that of aniline is C6H5CH2CONH2. The aniline molecule contains a benzene ring, which makes its physical and chemical properties different from ethylamine.

2. chemical reaction characteristics

1. reaction with NaOH solution

• ethylamine: The reaction of ethylamine with NaOH solution will produce the corresponding salt and water. The reaction equation is: CH3CH2CONH2 NaOH → CH3CH2CONa H2O.
• Aniline: The reaction of aniline with NaOH solution will also produce the corresponding salt and water, but due to the presence of the benzene ring, the reaction rate may be faster.

1. Reaction with water

• ethylamine ethylamine is slightly soluble in water, but can partially react with water to form an aqueous solution of ethylamine.
• Aniline aniline is insoluble in water, but can partially react with water to form an aqueous solution of aniline.

1. Reaction with acidic potassium permanganate

• ethylamine ethylamine does not react with acidic highly stabbing potassium permanganate.
• Aniline aniline can react with acidic potassium permanganate to form corresponding salts and gases (such as NH3).

3. other chemical tests

1. acid and alkaline strength

• ethylamine is less acidic than aniline, which can be distinguished by the reaction rate with NaOH solution.

1. Inhibition of nitrifying bacteria

• ethylamine and aniline both have antimicrobial effects, but the inhibitory effect of ethylamine is stronger. It can be distinguished by culture experiments on nitrifying bacteria.

Distinguishing methods in practical application of 4.

1. Solubility Test

• the substance to be tested is added to water and its dissolution is observed. Ethylamine is slightly soluble in water, while aniline is almost insoluble.

1. Density determination

• the density of the substances to be measured is measured by a hydrometer, the density of ethylamine is about 0.74g/cm³, while that of aniline is about 1.02g/cm³.

1. Reactions with acidic potassium permanganate

• the substance to be tested is added to the acidic potassium permanganate solution to observe whether bubbles are generated. Aniline reacts with acidic potassium permanganate to produce NH3 gas, while ethylamine does not.

5. Summary

ethylamine and aniline can be easily distinguished by the above chemical methods. Ethylamine is slightly soluble in water, with low density, and does not react with acidic potassium permanganate; while aniline is insoluble in water, with high density, and can react with acidic potassium permanganate and release NH3 gas. Understanding these chemical properties helps to accurately identify these two substances in practical applications.