Key Difference – Ethanol vs Ethanoic Acid
Although Ethanol and Ethanoic acid have similar names, a key difference can be observed between them as they are two different organic compounds containing two different functional groups. Ethanol is the second simplest member of the alcohol family whereas ethanoic acid is the second simplest member of the carboxylic acid group. They both contain only two Carbon atoms in addition to the functional group present in the molecule. When we compare their chemical properties; both of them are used as organic solvents and possess a characteristic smell. In contrast, ethanoic acid is more acidic than ethanol.
What is Ethanol?
The common name of ethanol is ethyl alcohol. Its functional group is a hydroxyl group (-OH group). All chemical properties such as reactivity, acidity or basicity depend on the functional group. Ethanol has a very mild smell, and it is a volatile compound. Ethanol is very important in its industrial applications; it is a safe solvent, a fuel source, used to produce medicines and cosmetics and it is the main component in alcoholic drinks. Ethanol can be produced domestically using agricultural waste such as corn, sugar cane, or grasses.
What is Ethanoic acid?
The most commonly used name for Ethanoic acid is acetic acid. It is a colourless liquid with a characteristic sour taste and pungent odour. It has the molecular formula of CH3COOH. The undiluted form of the ethanoic acid is called “glacial acetic acid” and roughly about 3-9% of acid by volume is used to make vinegar. Ethanoic acid is considered as a weak acid; but, it is corrosive and able to attack the skin.
What is the difference between Ethanol and Ethanoic acid?
Characteristics of Ethanol and Ethanoic acid:
Ethanol: Hydroxyl group (-OH group) is the functional group in ethanol. It is the characteristic property of alcohols. All alcohols have at least one –OH group in their structure.
Ethanoic acid: The functional group in ethanoic acid is a –COOH group. It is common for all carboxylic acids.
Ethanol: Ethanol is a monohydric alcohol with a sweet smell which boils at 78.5°C. It is the only hydrocarbon which dissolves in water in all proportions. Ethanol reacts with alkaline KMnO4 to give ethanoic acid while ethanoic acid does not react with alkaline KMnO4.
Ethanoic acid: It is a weak monoprotic acid in aqueous solution (pKa=4.76). Liquid acetic acid is a polar solvent like water. It dissolves both polar liquids such as sugars and salts, and non-polar liquids such as oils and elements like sulphur and iodine. It is readily and completely miscible with water chloroform, and hexane. Acetic acid has a strong pungent smell.
Ethanol: Ethanol is present in alcoholic drinks and also used as a biofuel for cars. It is a good solvent which can dissolve many organic solutions that are insoluble in water. Ethanol is used to manufacture many perfumes, cosmetics, and varnishes in the paint industry.
Ethanol as fuel:
CH3CH2OH + 3O2 → 2CO2 + 3H2O
Ethanoic acid: Acetic acid is used as a chemical reagent to produce other chemicals. It is used in larger quantities to produce vinyl acetate monomer; vinyl acetate can be polymerized to produce polyvinyl chloride or other polymers. In addition, acetic acid is used to produce esters which are used in inks, paintings and coatings. Acetic anhydride is another important chemical compound that can be synthesized by condensing two molecules of acetic acid. A small amount of ethanoic acid is used to produce household vinegar.
Ethanol: Ethanol neither reacts with Sodium bicarbonate (NaHCO₃) nor changes the colour of a blue litmus paper. Therefore, it is less acidic than ethanoic acid.
Ethanoic acid: Ethanoic acid is a weak acid which reacts with Sodium bicarbonate (NaHCO₃) releasing CO2 gas. Also, it turns blue litmus into red.Image Courtesy: “Ethanol-3D-balls”. (Public Domain) via Wikimedia Commons “Acetic acid dimer 3D ball” by Jynto (talk) – Own work.(CC0) via Wikimedia Commons