Ethanol acetaldehyde acetic acid how to distinguish

In chemical production and application, the three substances, ethanol, acetaldehyde and acetic acid, are often the focus of chemical personnel to understand and distinguish because of their similarities in structure and properties. As basic chemical materials, they play an important role in organic synthesis, environmental degradation, energy conversion and other fields. This article will analyze these three substances in depth from the aspects of structure, nature and use, so as to help practitioners in the chemical industry to accurately distinguish their differences.

1. and Properties of Ethanol

Ethanol (ethanol) is a colorless, tasteless (or, if odorous, exotic pea) liquid with the formula C2H5OH. It consists of two carbon atoms, with the hydroxyl group (-OH) located on the second carbon. Ethanol is an amphibian compound of strong polar acid and weak base, which can exist in two forms in aqueous solution, namely, ionic form and molecular form.

Physical properties: Ethanol is easily soluble in water and organic solvents, has a low density, and the density is 0.789g/cm3 at room temperature. It has a mild ratio of 0 at 20 degrees C, and can float on the water at 20 degrees C.

Chemical properties: ethanol and many substances occur addition, oxidation, dehydration and other reactions. Under the action of catalyst, ethanol can be dehydrated to produce ether; under acidic conditions, ethanol can be oxidized to acetaldehyde; under alkaline conditions, ethanol can be converted to sodium ethoxide.

Uses: Ethanol is widely used in alcohol production, solvent use, biodegradable material preparation and other fields. In the environmental field, ethanol is often used as a raw material for biofuels.

2. and Properties of Acetaldehyde

Acetaldehyde (acetaldehyde) is a colorless gas with the formula CH3CHO. It has a strong aldehyde odor and is easily soluble in water and organic solvents. Acetaldehyde is structurally similar to ethanol, but has an additional aldehyde group (-CHO).

Physical Properties: Acetaldehyde is a gas under standard conditions and has a density of 0.718g/cm3. It has a mild ratio of 0.718 at 25°C and is often mixed with gases of similar density.

Chemical properties: acetaldehyde is easily oxidized to acetic acid under the action of catalyst. It also reacts with a variety of substances, such as reacting with alcohols under acidic conditions to form ethers and condensation reactions with aldehyde groups.

Uses: Acetaldehyde is mainly used as a solvent, catalyst carrier, and as an intermediate in organic synthesis. Acetaldehyde can be produced industrially by the oxidation of ethanol.

, 3. acetic acid structure and properties

Acetic acid (acetic acid) is a colorless, odorless liquid, the molecular formula is CH3COOH. It is one of the simplest organic acids and has strong acidity.

Physical properties: Acetic acid is liquid at room temperature and has a density of 1.046g/cm3. It has a mild ratio of 1.046 at 25°C and is slightly heavier than water.

Chemical properties: acetic acid is a stable organic acid, which does not react with basic substances under most conditions, but is prone to dissociation under strong acidic or alkaline conditions, generating acid ions and hydrogen ions.

Uses: Acetic acid is widely used in organic synthesis, food preservation, battery manufacturing and other fields. In the field of environmental protection, acetic acid is often used as a base material for the preparation of biodegradable materials.

4. how to distinguish between ethanol, acetaldehyde and acetic acid

1. structural analysis The molecular formulas of ethanol, acetaldehyde, and acetic acid are C2H5OH, CH3CHO, and CH3COOH, respectively. Their structural differences are evident from the variation of the molecular formula. The ethanol structure contains hydroxyl group, the acetaldehyde structure contains aldehyde group, and the acetic acid structure contains carboxylic acid group.

2. Physical Properties The density of ethanol is about 0.789g/cm3, the density of acetaldehyde is 0.718g/cm3, and the density of acetic acid is 1.046g/cm3. The density difference is large and can be initially distinguished by measuring the density of the liquid.

3. chemical reaction characteristics Ethanol is readily oxidized to acetaldehyde, which is further oxidized to acetic acid. By observing the oxidation reaction characteristics of the substances, their differences can be judged.

4. Smell Ethanol is tasteless (if there is a special smell, it is a special bean), acetaldehyde has a strong aldehyde smell, and acetic acid is tasteless.

5. Use A distinction can also be made according to the use of the substance. Ethanol is mostly used as solvent and biodegradable material, acetaldehyde is used as solvent and intermediate, acetic acid is used as acid and raw material of organic synthesis.

5. summary

Ethanol, acetaldehyde, and acetic acid are three common substances in chemical production. Although they have many similarities in structure and use, they can be effectively distinguished by molecular structure analysis, density differences, odor characteristics, and chemical reaction characteristics. Understanding the differences of these three substances is of great significance to the operation and application in chemical production. Practitioners in the chemical industry should master the characteristics of these substances through in-depth study and practice, so as to be handy in practical work and improve production efficiency and product quality.