🧪 Acetic Acid / Ethanoic Acid
Questions 1–17 – Detailed Answers & Explanations
Questions 1–17 – Detailed Answers & Explanations
📚 Important Related Questions – Q1 to Q17
1. Why is pure acetic acid known as glacial acetic acid?
✅ Answer
Pure acetic acid is called glacial acetic acid
because it freezes at about 16.6°C and forms
ice-like crystals on cooling.
💡 Detailed Explanation
Pure acetic acid is a colourless liquid at temperatures above
its freezing point. When it is cooled to about 16.6°C, it starts
to solidify and forms crystalline masses.
These crystals resemble ice or a glacier. Because of this
ice-like appearance, pure acetic acid is called
glacial acetic acid.
Pure CH₃COOH → Cooling → Ice-like crystals
🧠 Human Touch:
The word “glacial” is simply a clue about its appearance after freezing. It does not mean that the acid contains ice.
The word “glacial” is simply a clue about its appearance after freezing. It does not mean that the acid contains ice.
🎯 Exam Keywords:
Pure acetic acid → 16.6°C → ice-like crystals → Glacial acetic acid.
Pure acetic acid → 16.6°C → ice-like crystals → Glacial acetic acid.
2. What is glacial acetic acid?
✅ Answer
Glacial acetic acid is nearly pure or anhydrous acetic
acid.
💡 Detailed Explanation
The word “glacial” is used for the nearly water-free form of
acetic acid. It has a freezing point of about 16.6°C and forms
ice-like crystals when cooled.
It should not be confused with ordinary vinegar, which is a
dilute solution of acetic acid in water.
🧪 Easy Understanding:
Glacial acetic acid = nearly pure acetic acid.
Vinegar = dilute acetic acid solution.
Glacial acetic acid = nearly pure acetic acid.
Vinegar = dilute acetic acid solution.
3. What is the chemical formula of acetic acid?
✅ Answer
The chemical formula of acetic acid is
CH₃COOH.
💡 Detailed Explanation
Acetic acid can be written in condensed structural form as:
CH₃–COOH
The molecule contains:
Carbon: 2 atoms
Hydrogen: 4 atoms
Oxygen: 2 atoms Therefore, its molecular formula can also be written as:
C₂H₄O₂
🎯 Remember:
CH₃COOH = Acetic acid = Ethanoic acid.
CH₃COOH = Acetic acid = Ethanoic acid.
4. What is the IUPAC name of acetic acid?
✅ Answer
The IUPAC name of acetic acid is
ethanoic acid.
💡 Detailed Explanation
Acetic acid contains two carbon atoms and a carboxylic acid
functional group.
The systematic IUPAC name is therefore
ethanoic acid.
Acetic acid = Ethanoic acid
🧠 Easy Memory:
Acetic = common name.
Ethanoic = IUPAC name.
Acetic = common name.
Ethanoic = IUPAC name.
5. What is the freezing point of pure acetic acid?
✅ Answer
The freezing point of pure acetic acid is approximately
16.6°C.
💡 Detailed Explanation
When pure acetic acid is cooled to approximately 16.6°C, it
starts changing from liquid to solid.
The formation of ice-like crystals is responsible for the term
glacial acetic acid.
🎯 Most Important Number:
16.6°C = Freezing point of pure acetic acid.
16.6°C = Freezing point of pure acetic acid.
6. Why does acetic acid form ice-like crystals?
✅ Answer
Pure acetic acid forms ice-like crystals because it solidifies
at about 16.6°C.
💡 Detailed Explanation
On cooling below its freezing point, pure acetic acid changes
from a liquid into a crystalline solid.
The appearance of these crystals resembles ice, which explains
the term “glacial”.
🧊 Human Touch:
Think of water turning into ice. In a similar visual sense, pure acetic acid forms crystalline solid masses when sufficiently cooled.
Think of water turning into ice. In a similar visual sense, pure acetic acid forms crystalline solid masses when sufficiently cooled.
7. Is glacial acetic acid different from acetic acid?
✅ Answer
Chemically, both refer to CH₃COOH, but
“glacial acetic acid” specifically refers to the
nearly pure, water-free form.
💡 Detailed Explanation
Acetic acid can be present in solutions containing water.
For example, vinegar contains dilute acetic acid.
When acetic acid is nearly pure and contains very little water,
it is commonly called glacial acetic acid.
Quick Comparison:
Acetic acid → General name for CH₃COOH
Glacial acetic acid → Nearly pure acetic acid
Acetic acid → General name for CH₃COOH
Glacial acetic acid → Nearly pure acetic acid
8. What is the difference between vinegar and glacial acetic acid?
✅ Answer
Vinegar is a dilute aqueous solution of acetic acid,
whereas glacial acetic acid is nearly pure acetic acid.
💡 Detailed Explanation
| Vinegar | Glacial Acetic Acid |
|---|---|
| Dilute solution of acetic acid | Nearly pure acetic acid |
| Contains considerable water | Contains very little water |
| Commonly used in food | Used in laboratory and industrial applications |
| Not pure acetic acid | Nearly pure acetic acid |
🎯 Exam Point:
Vinegar ≠ Pure Acetic Acid.
Vinegar ≠ Pure Acetic Acid.
9. Which acid is present in vinegar?
✅ Answer
The main acid present in vinegar is
acetic acid (ethanoic acid).
💡 Detailed Explanation
Vinegar contains acetic acid dissolved in water.
The acetic acid is responsible for the characteristic sour taste
and sharp smell associated with vinegar.
Vinegar ≈ Dilute acetic acid + Water
🍶 Everyday Connection:
Vinegar is commonly encountered in food. Its characteristic sourness is mainly due to acetic acid.
Vinegar is commonly encountered in food. Its characteristic sourness is mainly due to acetic acid.
10. Is acetic acid a strong acid or weak acid?
✅ Answer
Acetic acid is a weak acid.
💡 Detailed Explanation
Acetic acid only partially ionises when dissolved in water.
CH₃COOH ⇌ CH₃COO⁻ + H⁺
Because ionisation is incomplete, it is classified as a weak acid.
A weak acid does not mean that the solution is necessarily very
dilute. It refers to the degree of ionisation in water.
🎯 Key Concept:
Weak acid → Partial ionisation in water.
Weak acid → Partial ionisation in water.
11. Which functional group is present in acetic acid?
✅ Answer
Acetic acid contains the
carboxyl group (–COOH).
💡 Detailed Explanation
The structure of acetic acid is:
CH₃–COOH
The –COOH portion is the carboxyl group.
Therefore, acetic acid belongs to the family of
carboxylic acids.
🧠 Easy Understanding:
Whenever an organic compound contains the –COOH group as its characteristic functional group, it is a carboxylic acid.
Whenever an organic compound contains the –COOH group as its characteristic functional group, it is a carboxylic acid.
12. What happens when acetic acid reacts with sodium hydroxide?
✅ Answer
Acetic acid reacts with sodium hydroxide to form
sodium acetate and water.
CH₃COOH + NaOH → CH₃COONa + H₂O
💡 Detailed Explanation
This is an example of an
acid-base neutralisation reaction.
Here:
Acetic acid = Acid
Sodium hydroxide = Base
Sodium acetate = Salt
Water = Product
🧪 Human Touch:
The basic idea of neutralisation is that an acid reacts with a base to produce a salt and water.
The basic idea of neutralisation is that an acid reacts with a base to produce a salt and water.
🎯 Remember:
Acid + Base → Salt + Water.
Acid + Base → Salt + Water.
13. What happens when acetic acid reacts with sodium bicarbonate?
✅ Answer
Acetic acid reacts with sodium bicarbonate to form
sodium acetate, water and carbon dioxide gas.
CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂
💡 Detailed Explanation
When acetic acid reacts with sodium bicarbonate, carbon dioxide
gas is released.
This gas causes visible bubbling or effervescence.
General Pattern:
Acid + Sodium bicarbonate → Salt + Water + CO₂
Acid + Sodium bicarbonate → Salt + Water + CO₂
🧪 Practical Understanding:
The fizzing or bubbling seen during this type of reaction is caused by the rapid release of carbon dioxide gas.
The fizzing or bubbling seen during this type of reaction is caused by the rapid release of carbon dioxide gas.
14. Which gas is evolved when acetic acid reacts with sodium bicarbonate?
✅ Answer
Carbon dioxide (CO₂) gas is evolved.
💡 Detailed Explanation
The reaction is:
CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂
The evolved gas is carbon dioxide.
Carbon dioxide can be tested by passing it through limewater.
It turns limewater milky.
CO₂ + Ca(OH)₂ → CaCO₃ + H₂O
The milky appearance is due to the formation of calcium carbonate.
🎯 Exam Shortcut:
Acetic acid + NaHCO₃ → CO₂.
Acetic acid + NaHCO₃ → CO₂.
15. What happens when acetic acid reacts with sodium carbonate?
✅ Answer
Acetic acid reacts with sodium carbonate to produce
sodium acetate, water and carbon dioxide.
2CH₃COOH + Na₂CO₃
→ 2CH₃COONa + H₂O + CO₂
💡 Detailed Explanation
Sodium carbonate contains the carbonate ion. When an acid reacts
with a carbonate, carbon dioxide gas is released.
The products are:
Salt: Sodium acetate
Liquid: Water
Gas: Carbon dioxide
🧠 Easy Understanding:
Both sodium carbonate and sodium bicarbonate give carbon dioxide when they react with an acid.
Both sodium carbonate and sodium bicarbonate give carbon dioxide when they react with an acid.
🎯 Exam Trick:
Acid + Carbonate → Salt + Water + CO₂
Acid + Bicarbonate → Salt + Water + CO₂
Acid + Carbonate → Salt + Water + CO₂
Acid + Bicarbonate → Salt + Water + CO₂
16. What happens when acetic acid reacts with an active metal?
✅ Answer
Acetic acid reacts with a suitable active metal to form a
metal acetate and hydrogen gas.
2CH₃COOH + Mg → (CH₃COO)₂Mg + H₂
💡 Detailed Explanation
In this example, acetic acid reacts with magnesium.
The magnesium displaces hydrogen from the acid, producing
magnesium acetate and hydrogen gas.
The general reaction can be written as:
Acid + Active Metal → Salt + Hydrogen
For magnesium:
Acetic acid + Magnesium → Magnesium acetate + Hydrogen
🧪 Human Touch:
The release of hydrogen can be represented as gas formation during the reaction. The important examination point is the general pattern: acid reacting with a suitable active metal produces a salt and hydrogen.
The release of hydrogen can be represented as gas formation during the reaction. The important examination point is the general pattern: acid reacting with a suitable active metal produces a salt and hydrogen.
🎯 Remember:
Acid + Metal → Salt + H₂
Acid + Metal → Salt + H₂
17. What is the nature of acetic acid?
✅ Answer
Acetic acid is a weak organic acid and belongs
to the family of carboxylic acids.
💡 Detailed Explanation
Acetic acid has the formula:
CH₃COOH
It contains the characteristic carboxyl group:
–COOH
When dissolved in water, acetic acid only partially ionises:
CH₃COOH ⇌ CH₃COO⁻ + H⁺
Because the ionisation is incomplete, acetic acid is classified
as a weak acid.
👨🏫 Human Touch:
Acetic acid is a good example of a weak acid that we encounter in everyday life through vinegar. Its weak nature is related to its partial ionisation in water.
Acetic acid is a good example of a weak acid that we encounter in everyday life through vinegar. Its weak nature is related to its partial ionisation in water.
🎯 Exam Shortcut:
Acetic acid → Organic acid → Carboxylic acid → Weak acid
Acetic acid → Organic acid → Carboxylic acid → Weak acid
🔥 Questions 1–17 – Quick Revision
Q1. Pure acetic acid is called glacial acetic acid because it freezes at about 16.6°C and forms ice-like crystals.
Q2. Glacial acetic acid = nearly pure/anhydrous acetic acid.
Q3. Formula of acetic acid = CH₃COOH.
Q4. IUPAC name = Ethanoic acid.
Q5. Freezing point = 16.6°C.
Q6. Ice-like crystals form because pure acetic acid solidifies on cooling.
Q7. Glacial acetic acid refers specifically to the nearly pure form.
Q8. Vinegar is dilute acetic acid; glacial acetic acid is nearly pure.
Q9. Main acid in vinegar = Acetic acid.
Q10. Acetic acid = Weak acid.
Q11. Functional group = –COOH.
Q12. CH₃COOH + NaOH → CH₃COONa + H₂O.
Q13. CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂.
Q14. Gas evolved with NaHCO₃ = CO₂.
Q15. Acetic acid + Na₂CO₃ → Sodium acetate + Water + CO₂.
Q16. Acetic acid + suitable active metal → Metal acetate + H₂.
Q17. Nature of acetic acid = Weak organic carboxylic acid.
Q2. Glacial acetic acid = nearly pure/anhydrous acetic acid.
Q3. Formula of acetic acid = CH₃COOH.
Q4. IUPAC name = Ethanoic acid.
Q5. Freezing point = 16.6°C.
Q6. Ice-like crystals form because pure acetic acid solidifies on cooling.
Q7. Glacial acetic acid refers specifically to the nearly pure form.
Q8. Vinegar is dilute acetic acid; glacial acetic acid is nearly pure.
Q9. Main acid in vinegar = Acetic acid.
Q10. Acetic acid = Weak acid.
Q11. Functional group = –COOH.
Q12. CH₃COOH + NaOH → CH₃COONa + H₂O.
Q13. CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂.
Q14. Gas evolved with NaHCO₃ = CO₂.
Q15. Acetic acid + Na₂CO₃ → Sodium acetate + Water + CO₂.
Q16. Acetic acid + suitable active metal → Metal acetate + H₂.
Q17. Nature of acetic acid = Weak organic carboxylic acid.
🧠 One-Line Memory Chart
CH₃COOH → Acetic acid / Ethanoic acid
–COOH → Carboxyl group
16.6°C → Freezing point of pure acetic acid
Glacial acetic acid → Nearly pure acetic acid
Vinegar → Dilute aqueous acetic acid
NaOH → Sodium acetate + Water
NaHCO₃ → CO₂ released
Na₂CO₃ → CO₂ released
Active metal → Hydrogen gas released
Nature → Weak acid
–COOH → Carboxyl group
16.6°C → Freezing point of pure acetic acid
Glacial acetic acid → Nearly pure acetic acid
Vinegar → Dilute aqueous acetic acid
NaOH → Sodium acetate + Water
NaHCO₃ → CO₂ released
Na₂CO₃ → CO₂ released
Active metal → Hydrogen gas released
Nature → Weak acid
🧪 Acetic Acid / Ethanoic Acid
Questions 17–30 – Detailed Answers & Explanations
Questions 17–30 – Detailed Answers & Explanations
📚 Important Related Questions – Q17 to Q30
17. What is the nature of acetic acid?
✅ Answer
Acetic acid is a **weak organic acid**. It belongs to the
family of **carboxylic acids**.
💡 Detailed Explanation
Acetic acid contains the carboxyl group **–COOH**, which gives
it acidic properties.
Its formula is:
CH₃COOH
When dissolved in water, acetic acid ionises only partially:
CH₃COOH ⇌ CH₃COO⁻ + H⁺
Because it does not completely ionise in water, acetic acid is
classified as a **weak acid**.
👨🏫 Human Touch:
A weak acid should not be confused with an acid that is simply “less acidic” because it is dilute. The term weak refers mainly to the extent to which the acid ionises in water.
A weak acid should not be confused with an acid that is simply “less acidic” because it is dilute. The term weak refers mainly to the extent to which the acid ionises in water.
🎯 Remember:
Acetic acid = Organic acid + Carboxylic acid + Weak acid.
Acetic acid = Organic acid + Carboxylic acid + Weak acid.
18. What is the functional group of carboxylic acids?
✅ Answer
The functional group of carboxylic acids is the
carboxyl group (–COOH).
💡 Detailed Explanation
A functional group is an atom or group of atoms responsible for
the characteristic chemical properties of an organic compound.
The carboxylic acid functional group is:
–COOH
In acetic acid:
CH₃–COOH
The **–COOH** portion is the carboxyl group.
Examples of carboxylic acids include:
| Compound | Formula | Functional Group |
|---|---|---|
| Formic acid | HCOOH | –COOH |
| Acetic acid | CH₃COOH | –COOH |
| Propionic acid | CH₃CH₂COOH | –COOH |
🧠 Easy Understanding:
Whenever you see –COOH attached to an organic molecule, think carboxylic acid.
Whenever you see –COOH attached to an organic molecule, think carboxylic acid.
19. What are the common name and IUPAC name of CH₃COOH?
✅ Answer
Common name: Acetic acid
IUPAC name: Ethanoic acid
💡 Detailed Explanation
CH₃COOH is a two-carbon carboxylic acid.
Its commonly used traditional name is **acetic acid**, while
its systematic IUPAC name is **ethanoic acid**.
CH₃COOH = Acetic acid = Ethanoic acid
The word **ethanoic** comes from the two-carbon parent chain
(ethane) combined with the carboxylic acid suffix.
🎯 Exam Shortcut:
If the question asks:
CH₃COOH → Ethanoic acid
Acetic acid → CH₃COOH
If the question asks:
CH₃COOH → Ethanoic acid
Acetic acid → CH₃COOH
20. What is the molecular formula of ethanoic acid?
✅ Answer
The molecular formula of ethanoic acid is:
CH₃COOH
It can also be written as:
C₂H₄O₂
💡 Detailed Explanation
CH₃COOH is the condensed structural formula.
Counting the atoms gives:
- Carbon = 2
- Hydrogen = 4
- Oxygen = 2
🧠 Human Touch:
Do not confuse the structural/condensed formula CH₃COOH with the molecular formula C₂H₄O₂. Both represent the same compound.
Do not confuse the structural/condensed formula CH₃COOH with the molecular formula C₂H₄O₂. Both represent the same compound.
21. At what temperature does glacial acetic acid freeze?
✅ Answer
Glacial acetic acid freezes at approximately
16.6°C.
💡 Detailed Explanation
Nearly pure acetic acid has a freezing point of about
16.6°C.
When the temperature falls below this point, the liquid
acetic acid starts changing into a solid crystalline form.
Pure CH₃COOH → Cooling to about 16.6°C → Solid crystals
The resulting crystals can resemble ice, which is why the
term **glacial** is used.
🎯 Most Important Number:
16.6°C = Freezing point of pure acetic acid.
16.6°C = Freezing point of pure acetic acid.
22. Why is acetic acid called “glacial”?
✅ Answer
It is called **glacial acetic acid** because pure acetic acid
freezes at about 16.6°C and forms **ice-like crystals**.
💡 Detailed Explanation
The word “glacial” refers to the ice-like appearance of the
crystals formed when pure acetic acid solidifies.
It does not mean that the acid contains ice.
🧠 Easy Memory Trick:
Think:
Glacial → Glacier → Ice → Acetic acid crystals
Think:
Glacial → Glacier → Ice → Acetic acid crystals
23. What is the main acid present in vinegar?
✅ Answer
The main acid present in vinegar is
acetic acid (ethanoic acid).
💡 Detailed Explanation
Vinegar is essentially a dilute aqueous solution containing
acetic acid.
The acetic acid is responsible for its characteristic
sour taste and pungent smell.
Vinegar = Dilute acetic acid + Water
🍶 Human Touch:
The familiar sour taste of vinegar is something we encounter in everyday food. Chemically, the important acid responsible for this characteristic is acetic acid.
The familiar sour taste of vinegar is something we encounter in everyday food. Chemically, the important acid responsible for this characteristic is acetic acid.
🎯 Remember:
Vinegar → Acetic acid → Ethanoic acid.
Vinegar → Acetic acid → Ethanoic acid.
24. What is the IUPAC name of acetic acid?
✅ Answer
The IUPAC name of acetic acid is
ethanoic acid.
💡 Detailed Explanation
Acetic acid contains two carbon atoms and a carboxylic acid
functional group.
The two-carbon parent name is **ethane**. With the carboxylic
acid naming system, the compound is called **ethanoic acid**.
Acetic acid → Ethanoic acid
🎯 Exam Trick:
Remember the pair:
Acetic = Common name
Ethanoic = IUPAC name
Remember the pair:
Acetic = Common name
Ethanoic = IUPAC name
25. What is the formula of ethanoic acid?
✅ Answer
The formula of ethanoic acid is:
CH₃COOH
Its molecular formula is:
C₂H₄O₂
💡 Detailed Explanation
The condensed formula **CH₃COOH** clearly shows the carboxyl
group.
The atoms can be counted as:
C: 2H: 4
O: 2 Therefore: CH₃COOH = C₂H₄O₂
🧪 Human Touch:
Writing CH₃COOH is often more useful in chemical reactions because it shows the reactive –COOH group directly.
Writing CH₃COOH is often more useful in chemical reactions because it shows the reactive –COOH group directly.
26. Is acetic acid a weak acid?
✅ Answer
Yes. Acetic acid is a weak acid because it
only partially ionises in aqueous solution.
💡 Detailed Explanation
When acetic acid is dissolved in water, only a fraction of its
molecules ionise.
CH₃COOH ⇌ CH₃COO⁻ + H⁺
The double arrow indicates that the ionisation is reversible
and incomplete.
This partial ionisation is why acetic acid is classified as
a weak acid.
🧠 Important Concept:
“Weak acid” means partial ionisation. It does not simply mean “dilute acid”.
“Weak acid” means partial ionisation. It does not simply mean “dilute acid”.
27. Which functional group does acetic acid contain?
✅ Answer
Acetic acid contains the
carboxyl group (–COOH).
💡 Detailed Explanation
The structure of acetic acid is:
CH₃–COOH
The group **–COOH** is called the carboxyl group.
Because acetic acid contains this group, it belongs to the
family of **carboxylic acids**.
🎯 Quick Connection:
–COOH → Carboxyl group → Carboxylic acid
–COOH → Carboxyl group → Carboxylic acid
28. What gas is released when acetic acid reacts with NaHCO₃?
✅ Answer
Carbon dioxide (CO₂) gas is released.
💡 Detailed Explanation
Acetic acid reacts with sodium bicarbonate to produce sodium
acetate, water and carbon dioxide.
CH₃COOH + NaHCO₃
→ CH₃COONa + H₂O + CO₂
The release of CO₂ produces visible bubbling or effervescence.
The gas can be tested using limewater. Carbon dioxide turns
limewater milky:
CO₂ + Ca(OH)₂ → CaCO₃ + H₂O
🧪 Practical Understanding:
If you see fizzing when an acid reacts with a carbonate or bicarbonate, the gas being released is commonly carbon dioxide.
If you see fizzing when an acid reacts with a carbonate or bicarbonate, the gas being released is commonly carbon dioxide.
🎯 Remember:
Acid + NaHCO₃ → CO₂
Acid + NaHCO₃ → CO₂
29. What salt is produced when acetic acid reacts with NaOH?
✅ Answer
The salt produced is
sodium acetate (CH₃COONa).
💡 Detailed Explanation
Acetic acid reacts with sodium hydroxide in a neutralisation
reaction.
CH₃COOH + NaOH → CH₃COONa + H₂O
Here:
CH₃COOH = Acetic acid
NaOH = Sodium hydroxide
CH₃COONa = Sodium acetate
H₂O = Water
🧠 Human Touch:
The easiest way to understand this reaction is: the acid and base react together, producing a salt and water. This is a standard example of neutralisation.
The easiest way to understand this reaction is: the acid and base react together, producing a salt and water. This is a standard example of neutralisation.
🎯 Exam Shortcut:
Acetic acid + NaOH = Sodium acetate + Water.
Acetic acid + NaOH = Sodium acetate + Water.
30. What is vinegar?
✅ Answer
Vinegar is a **dilute aqueous solution of acetic acid
(ethanoic acid)**.
💡 Detailed Explanation
Vinegar contains acetic acid dissolved in water. Therefore,
vinegar should not be confused with pure acetic acid.
Vinegar ≈ Dilute CH₃COOH solution
The concentration of acetic acid varies among different
vinegars, but it is much more dilute than glacial acetic acid.
🍶 Everyday Connection:
Vinegar is commonly used in food. Its characteristic sour taste comes mainly from the acetic acid present in the solution.
Vinegar is commonly used in food. Its characteristic sour taste comes mainly from the acetic acid present in the solution.
🎯 Remember:
Vinegar = Acetic acid + Water
Glacial acetic acid = Nearly pure acetic acid
Vinegar = Acetic acid + Water
Glacial acetic acid = Nearly pure acetic acid
🔥 Q17–Q30 Quick Revision
17. Nature of acetic acid → Weak organic acid
18. Functional group → –COOH, carboxyl group
19. CH₃COOH → Acetic acid / Ethanoic acid
20. Molecular formula → C₂H₄O₂, condensed formula CH₃COOH
21. Freezing point → 16.6°C
22. Why glacial? → Ice-like crystals on freezing
23. Acid in vinegar → Acetic acid
24. IUPAC name → Ethanoic acid
25. Formula → CH₃COOH
26. Weak acid? → Yes
27. Functional group → –COOH
28. CH₃COOH + NaHCO₃ → CO₂ released
29. CH₃COOH + NaOH → Sodium acetate + Water
30. Vinegar → Dilute aqueous solution of acetic acid
18. Functional group → –COOH, carboxyl group
19. CH₃COOH → Acetic acid / Ethanoic acid
20. Molecular formula → C₂H₄O₂, condensed formula CH₃COOH
21. Freezing point → 16.6°C
22. Why glacial? → Ice-like crystals on freezing
23. Acid in vinegar → Acetic acid
24. IUPAC name → Ethanoic acid
25. Formula → CH₃COOH
26. Weak acid? → Yes
27. Functional group → –COOH
28. CH₃COOH + NaHCO₃ → CO₂ released
29. CH₃COOH + NaOH → Sodium acetate + Water
30. Vinegar → Dilute aqueous solution of acetic acid
🧠 Super-Fast Exam Revision
Acetic Acid: CH₃COOH
IUPAC Name: Ethanoic acid
Functional Group: –COOH
Nature: Weak acid
Freezing Point: 16.6°C
Glacial Acetic Acid: Nearly pure acetic acid
Vinegar: Dilute aqueous acetic acid
With NaOH: Sodium acetate + Water
With NaHCO₃: Sodium acetate + Water + CO₂
Gas evolved: CO₂
IUPAC Name: Ethanoic acid
Functional Group: –COOH
Nature: Weak acid
Freezing Point: 16.6°C
Glacial Acetic Acid: Nearly pure acetic acid
Vinegar: Dilute aqueous acetic acid
With NaOH: Sodium acetate + Water
With NaHCO₃: Sodium acetate + Water + CO₂
Gas evolved: CO₂