high importancemedium8 min

Ethanoic Acid

Ethanoic acid is a carboxylic acid with formula CH3COOH.

Practice This Concept

Learn the concept

Student-friendly explanation

How to write this in exams

1
Start with the exact idea
Ethanoic acid is a carboxylic acid with formula CH₃COOH.
2
Then show how to use it
1. Locate the -COOH group. 2. Name the compound as a carboxylic acid. 3. Recall its acidic reactions. 4. Distinguish it from ethanol by the presence of the carboxyl group.
3
Add one concrete example
CH₃COOH reacts with sodium hydrogen carbonate to release carbon dioxide gas, showing its acidic nature.
4
Avoid this incomplete answer
A common wrong answer is to identify CH₃CH₂OH as ethanoic acid. That is wrong because it is ethanol and does not contain -COOH.

Definition

Ethanoic acid is a carboxylic acid with formula CH₃COOH.

Example

CH₃COOH reacts with sodium hydrogen carbonate to release carbon dioxide gas, showing its acidic nature.

Rule to remember

Ethanoic acid has the formula CH₃COOH. The key group is -COOH. It reacts with bases and carbonates, and it is a weak acid compared with mineral acids.

Memory hook

COOH at the end means acid.

Examples and method

Worked example

When ethanoic acid reacts with sodium hydrogen carbonate, carbon dioxide gas is released. This reaction is commonly used to show the presence of an acid in school experiments.

Method to apply

1. Locate the -COOH group. 2. Name the compound as a carboxylic acid. 3. Recall its acidic reactions. 4. Distinguish it from ethanol by the presence of the carboxyl group.

Diagram support

Write the structure as CH3-C(=O)-OH so the carboxyl group is easy to see.

How CBSE asks it

Questions may ask for the formula, the functional group, the reaction with carbonates, or the difference between ethanol and ethanoic acid.

Avoid common mistakes

Common confusion

Students often confuse ethanoic acid with ethanol because both contain carbon, hydrogen, and oxygen.

Common wrong answer

A common wrong answer is to identify CH₃CH₂OH as ethanoic acid. That is wrong because it is ethanol and does not contain -COOH.

Exam tip

Whenever you see -COOH, think carboxylic acid and acidic behaviour.

Quick check

Which functional group gives ethanoic acid its acidic nature?

The carboxyl group -COOH gives ethanoic acid its acidic nature. That group is the main reason the compound behaves like an acid.

Answer writing and exam use

1-mark answer

Ethanoic acid is a carboxylic acid with formula CH₃COOH.

2-mark answer

Ethanoic acid is a carboxylic acid with formula CH₃COOH. Ethanoic acid has the formula CH₃COOH. The key group is -COOH. It reacts with bases and carbonates, and it is a weak acid compared with mineral acids. CH₃COOH reacts with sodium hydrogen carbonate to release carbon dioxide gas, showing its acidic nature.

3-mark answer

Ethanoic acid is the acid found in vinegar in dilute form. Its special group is -COOH, which gives acidic properties. It reacts with bases and carbonates, so it is an important example for understanding acid behaviour in organic chemistry. Students should also remember that it is a weak acid, not a strong mineral acid. Ethanoic acid has the formula CH₃COOH. The key group is -COOH. It reacts with bases and carbonates, and it is a weak acid compared with mineral acids. When ethanoic acid reacts with sodium hydrogen carbonate, carbon dioxide gas is released. This reaction is commonly used to show the presence of an acid in school experiments. Questions may ask for the formula, the functional group, the reaction with carbonates, or the difference between ethanol and ethanoic acid. A common wrong answer is to identify CH₃CH₂OH as ethanoic acid. That is wrong because it is ethanol and does not contain -COOH.

MCQ Quiz

Practice this concept with focused MCQs

Open the concept quiz intro first, review the test details, and then start a focused MCQ set from this concept only. Instant score and answer review are live now.

10 MCQs5 MinutesInstant Results