Test for the identification of phenol and ethanol

How to carry out phenol and ethanol identification test?

In chemical experiments, phenol and ethanol are two common organic compounds. Their chemical properties and uses are quite different, but because of their similar appearance, they often need to be distinguished by some special identification tests. This article will introduce in detail how to carry out the identification test of phenol and ethanol to help chemical practitioners or students to identify these two substances more accurately.

PHENOL AND ETHANOL PHYSICAL PROPERTIES COMPARATIVE

Phenol and ethanol have some similarities in physical properties, for example, they are both miscible with water and are both liquids at room temperature. There are also obvious differences between the two. Phenol has a relatively high boiling point of about 182°C, while ethanol has a boiling point of 78.37°C. Therefore, in the identification test of phenol and ethanol, the temperature difference can be used as the basis for preliminary judgment.

Use of potassium ferricyanide reagent to identify phenol and ethanol

Potassium ferricyanide reagent is a commonly used reagent to distinguish between phenol and ethanol. The specific operation steps are as follows: a small amount of the substance to be tested (phenol or ethanol) is added dropwise to the potassium ferricyanide reagent, and the phenol solution will show a clear blue or green reaction, while ethanol has no significant reaction. This reaction is due to the complexation reaction between the phenolic hydroxyl group of phenol and the iron ion in potassium ferricyanide to form a complex with color change. Therefore, the potassium ferricyanide reagent can effectively distinguish between phenol and ethanol.

Acidic test: Phenol and ethanol reaction difference

The acidity difference between phenol and ethanol is an important basis for the identification test. The phenol molecule contains a phenolic hydroxyl (-OH), which has strong acidity and can react with metal sodium to release hydrogen. Ethanol is relatively mild, the reaction is relatively slow. If sodium metal is added to the test tube, phenol will quickly react with sodium to produce bubbles and release hydrogen, while ethanol will react more slowly and produce fewer bubbles. Through this experiment, we can clearly distinguish between phenol and ethanol.

Ferric chloride test: Phenol characteristic reaction

Ferric chloride solution is a common reagent for the identification of phenol. When phenol is mixed with a ferric chloride solution, the phenol reacts with ferric ions to form a purple complex with a significant color change. Ethanol does not have a similar reaction, so this method can also effectively distinguish between phenol and ethanol.

Summary

The identification test of phenol and ethanol mainly depends on the difference of their chemical properties. These two substances can be accurately distinguished by potassium ferricyanide reagent reaction, metal sodium reaction and ferric chloride reaction. During the experiment, we need to combine the physical properties and the results of chemical reactions to make accurate judgments. Understanding these identification methods is essential for the accuracy and reliability of chemical experiments.

Through the analysis of this paper, it is hoped that it can help readers to master how to carry out the identification test of phenol and ethanol, and provide reference for the development of chemical related work.