CBSE Chemistry Experiment Properties of Acetic Acid Experiment

Chemistry Experiment - Properties Of Acetic Acid Experiment

Acetic acid is also known as ethanoic acid, vinegar acid, ethylic acid, and methane carboxylic acid. It is a clear, organic, colourless liquid with a pungent odour similar to household vinegar. It has a variety of uses, including as raw material and solvent in the preparation of other chemical products, oil and gas production, and food and pharmaceutical industries.

Table of Contents 

• Aim

• Apparatus Required

• Theory 

• Procedure

• Observation Table

• Results

Aim

To study or determine the following properties of acetic acid or ethanoic acid-

1. Smell or Odour

2. Effect on litmus

3. Solubility in water

4. Reaction with sodium bicarbonate

Materials Required

1. Test tube

2. Beaker

3. Dropper

4. Litmus paper

5. Test tube stand

6. Distilled water

7. Acetic acid

8. Cork fit

9. Water

10. Sodium bicarbonate

11. Freshly prepared lime water

Theory

1. Acetic acid 

The chemical name of acetic acid is ethanoic acid, and it has the chemical formula CH3COOH. The COOH group is called the carboxylic group, which is responsible for the properties of ethanoic acid. It smells like vinegar and dissolves in water.

2. Glacial Acetic acid

The acetic acid that contains a very little amount of water that is less than 1% is called anhydrous or water-free acetic acid or glacial acetic acid. Its melting point is 16.6 °C. The reason it is called glacial is that it solidifies into solid acetic acid crystals just cooler than room temperature at 16.6 °C, which is ice.

Procedure

1. To determine the odour:

• Take a test tube of measurement 10 mL.

• Then add 5 mL of ethanoic or acetic acid to it

• Bring the test tube near or close your nose and smell it by wafting it.

2. To check the solubility in water:

• Take a test tube of measurement 20 mL.

• Then add 2 mL of ethanoic or acetic acid to it

• Pour 10-15 mL of distilled water and stir or mix it.

3. To determine the effect on litmus:

• Take a clean (well-washed) dropper

• Take a blue litmus paper

• Pour 2-3 drops of ethanoic or acetic acid on the litmus paper.

4. Reaction with sodium bicarbonate:

• Take a test tube of measurement 5 mL.

• Add a pinch of sodium bicarbonate to it

• Then pour 1 mL of dilute ethanoic or acetic acid into the test tube.

• To the mouth of the test tube, fix a cork with a bent delivery tube

• The other end of the delivery tube is required to be dipped in lime water.

Observations

Result

• Acetic acid or ethanoic acid or glacial acetic acid smells like vinegar.

• Both acetic acid and glacial acetic acid are water-soluble.

• Acetic acid turns blue litmus paper to red colour.

• And, when acetic acid reacts or combines with sodium bicarbonate, carbon dioxide gas is liberated or released.

Precautions

1. Handle the solutions carefully.

2. Add a small amount of sodium bicarbonate.

3. Stay away from the vapours of the chemicals and try not to inhale them.

4. Lime water must be freshly prepared.

Lab Manual Questions

1. What are the other names for acetic acid?

Ans. Acetic acid is also known as ethanoic acid, vinegar acid, ethylic acid, and methane carboxylic acid.

2. How to measure the amount of acetic acid in vinegar?

Ans. We can calculate or measure the percent of acetic acid in vinegar by the given formula- \[\left( {\dfrac{{Mass\,of\,Acetic\,Acid}}{{Mass\,of\,Vinegar}}} \right) \times 100\].

3. In an experiment, one mole of acetic acid signifies.

Ans. One mole of acetic acid signifies the given amount or given mass of acetic acid is exactly equal to its molar or molecular mass.

4. How to take the acetic acid test?

Ans. We can take the acetic acid test by taking a blue litmus paper. If the solution turns the blue litmus to red, then the solution will be considered acetic acid.

Viva Questions

1. Name the functional group present in acetic acid.

Ans. Carboxylic acid is the functional group present in acetic acid.

2. Acetic acid: which types of acid, strong or weak?

Ans. Acetic acid is a weak acid.

3. At what temperature does glacial acetic acid freeze?

Ans. Glacial acetic acid freezes at 16.6 °C.

4. Name the alkyl group present in acetic acid.

Ans. The Methyl group is present in acetic acid.

5. Does acetic acid turn which colour of litmus to which colour?

Ans. Acetic acid turns blue litmus to red colour.

6. How to measure the amount of acetic acid in the vinegar?

Ans. To measure, the amount of acetic acid in vinegar can vary, typically between 4 to 6% for table vinegar, but up to three times higher (18%) for pickling vinegar.

7. Which gas is released when acetic acid reacts with sodium bicarbonate?

Ans. Carbon dioxide gas is released when acetic acid reacts with sodium bicarbonate.

8. What is the density of acetic acid in liquid form?

Ans. In the liquid form, the density of acetic acid is 1.049 g/cm³.

9. What is the boiling temperature of acetic acid?

Ans. The boiling temperature for acetic acid is 391K.

Practical Questions

1. The most preferred and usable form of acetic acid is-

1. Glacial acetic acid

2. Vinegar

3. Acetic anhydride

4. Chloroacetic acid

Ans. Vinegar is the most preferred and most usable form of acetic acid.

2. The pH value of vinegar is-

1. 2.5

2. 5

3. 7

4. 3.5

Ans. The pH value of vinegar is generally 3.5.

3. Name the form of acetic acid which forms an ice-like solid when the temperature is reduced-

1. Vinegar

2. Acetic anhydride

3. Glacial acetic acid

4. Chloroacetic acid

Ans. Glacial acetic acid is the form of acetic acid which forms an ice-like solid when the temperature is reduced.

4. When acetic acid reacts with metal ions, it liberates-

1. Acetic anhydride

2. Acetate salts

3. Chloroacetic acid

4. None of these

Ans. The formation of acetate salts takes place when acetic acid is exposed to the metal ion.

5. The malt vinegar can be prepared with the help of-

1. Acetate salts

2. Acetic acid

3. Fruit juice

4. Malted grain

Ans. The malt vinegar can be prepared from the malted grain.

6. Which of the following is the weak acid?

1. Acetic acid

2. Nitric acid

3. Hydrochloric acid

4. Sulphuric acid

Ans. Acetic acid is a weak acid, rest are strong acids.

7. Does acetic acid dissolve in water?

1. True

2. False

3. Not applicable

4. None of these

Ans. Acetic acid dissolves in water. So, it is true.

8. Acid releases, which ions in an aqueous solution.

1. H+ ions

2. OH- ions

3. No ions

4. None of these

Ans. Acid releases H+ ions in the aqueous solution.

Conclusion

From the above experiment, we can conclude that acetic acid has a pungent or vinegar-like smell, it turns blue litmus paper to red, it is soluble in water, and on reacting with sodium bicarbonate it releases carbon dioxide gas.