Class 10 Science Ch4 Notes Carbon & Its Compounds 2026 PDF

Carbon is one of the most fascinating elements in chemistry because it forms the backbone of life and countless materials we use every day. From fuels that power our homes and vehicles to medicines, plastics, and even the food we eat, carbon compounds are everywhere.

In this Class 10 Chemistry chapter notes, you will learn how carbon forms bonds, why it is so versatile, and how it can create an endless variety of compounds by linking with other elements and with itself.

You’ll also discover the difference between saturated and unsaturated compounds, and how we name them using the IUPAC system. The NCERT chapter will guide you through functional groups, important reactions of carbon compounds, and real-life examples like ethanol and ethanoic acid.

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You will also understand how soaps and detergents work to remove dirt and grease. By the end, you’ll see why carbon and its compounds are not just a topic in chemistry, but an essential part of our lives and the world around us.

Carbon and Its Compounds Class 10 Notes – NCERT Summary

According to CBSE class 10 science syllabus this chapter tells you how Carbon is one of the most important elements in chemistry. It is the basis of all living organisms and a major part of fuels, plastics, medicines, and countless materials we use every day.

The versatility of carbon comes from its ability to form a wide variety of compounds, ranging from simple molecules like methane to extremely complex molecules such as proteins and DNA. In this chapter, we study the bonding, properties, types, and reactions of carbon compounds, along with their importance in daily life.

To practice questions of this chapter, check out Class 10 Science NCERT Solutions.

Covalent Bond in Carbon

Atoms combine to form molecules by sharing or transferring electrons. Carbon forms bonds mainly by sharing electrons, resulting in covalent bonding.

Covalent bonds are formed when atoms share one or more pairs of electrons to complete their outermost shell (achieve stability like noble gases).

Carbon has an atomic number of 6 and an electronic configuration of 2, 4. This means it has four electrons in its outermost shell and needs four more to achieve the stable configuration of 8 electrons.

Instead of gaining or losing electrons (which would require a huge amount of energy), carbon shares its four valence electrons with other atoms. This property makes it tetravalent.

Example: In methane (CH₄), one carbon atom shares each of its four valence electrons with one hydrogen atom.

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Properties of Covalent Compounds

Covalent compounds, including most carbon compounds, have certain characteristic properties:

• They usually have low melting and boiling points because the forces between molecules (intermolecular forces) are weak.
• They are generally poor conductors of electricity because they do not have free ions or electrons to carry electric current.
• They are often insoluble in water but soluble in organic solvents like benzene.

Versatile Nature of Carbon - Catenation & Tetravalency

Carbon is called versatile because it can form an enormous number of compounds, much more than any other element. This is due to two main reasons:

1. Catenation: Catenation is the property of carbon atoms to link with other carbon atoms to form long chains, branched structures, or rings. This happens because the carbon–carbon bond is strong and stable. Examples: chains in propane (C₃H₈), ring in benzene (C₆H₆).

2. Tetravalency: Carbon’s ability to form four covalent bonds allows it to bond with different atoms like hydrogen, oxygen, nitrogen, sulfur, and halogens, as well as with other carbon atoms. This leads to a huge variety of structures - straight chains, branched chains, and rings.

Saturated and Unsaturated Carbon Compounds

Carbon compounds can be classified according to the type of bonds between carbon atoms.

• Saturated Compounds (Alkanes): These contain only single bonds between carbon atoms. They are generally less reactive. Example: methane (CH₄), ethane (C₂H₆), propane (C₃H₈).
  
  
• Unsaturated Compounds: These have double bonds (alkenes) or triple bonds (alkynes) between carbon atoms. They are more reactive than alkanes. Example: ethene (C₂H₄), ethyne (C₂H₂).

Chains, Branches, and Rings

Carbon can form:

• Straight chains (butane: C₄H₁₀)

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• Branched chains (isobutane)

• Rings (cyclohexane: C₆H₁₂; benzene: C₆H₆)

Functional Groups & Nomenclature

The IUPAC (International Union of Pure and Applied Chemistry) system is used for naming organic compounds.

Rules for Nomenclature:

1. Identify the longest continuous carbon chain.
2. Number the chain from the end nearest to the substituent.
3. Name the substituents and mention their positions.
4. Combine the name of the substituents with the base name.

Prefixes: indicate side chains or substituents (methyl-, ethyl-, etc.).

Suffixes:

• -ane for alkanes (single bond)
• -ene for alkenes (double bond)
• -yne for alkynes (triple bond)
• -ol for alcohols (-OH group)
• -al for aldehydes (-CHO group)
• -one for ketones (>C=O group)
• -oic acid for carboxylic acids (-COOH group)

Example: CH₃CH₂CH₂OH → propanol.

Functional Groups

A functional group is an atom or group of atoms in a molecule that determines its chemical properties.

Common functional groups:

• Alcohol (-OH)
• Aldehyde (-CHO)
• Ketone (>C=O)
• Carboxylic acid (-COOH)
• Halogen (-Cl, -Br, -I)

Important Reactions of Carbon Compounds

Carbon compounds show several types of chemical reactions:

1. Combustion

Carbon compounds burn in air (oxygen) to give carbon dioxide, water, heat, and light. Example: CH₄ + 2O₂ → CO₂ + 2H₂O + energy.

Saturated hydrocarbons burn with a clean flame, while unsaturated hydrocarbons produce a yellow, sooty flame due to incomplete combustion.

2. Oxidation

Some carbon compounds can be oxidized to give other compounds. Oxidizing agents like alkaline potassium permanganate (KMnO₄) or acidified potassium dichromate (K₂Cr₂O₇) are used.

Example: Ethanol → Ethanoic acid (using KMnO₄ or K₂Cr₂O₇)

3. Addition Reaction

Unsaturated hydrocarbons undergo addition reactions in which atoms are added to the carbon atoms involved in the double or triple bond.

Example: CH₂=CH₂ + H₂ → CH₃-CH₃ (using catalyst Ni/Pt/Pd)

4. Substitution Reaction

Saturated hydrocarbons react by substitution, where one atom is replaced by another.

Example: CH₄ + Cl₂ → CH₃Cl + HCl (in the presence of sunlight)

Ethanol and Ethanoic Acid

Two important carbon compounds studied in detail are ethanol and ethanoic acid.

Ethanol (C₂H₅OH)

• Physical properties: Colourless liquid, pleasant smell, soluble in water, boiling point 351 K.
• Uses:
  
  • As a solvent in medicines and perfumes.
  • As an alcoholic drink (beverages).
  • As fuel (in spirit lamps, as gasohol, and blended with petrol in automobiles).
• Harmful effects: Excess consumption affects brain functions, impairs judgment, and can damage the liver (cirrhosis) and nervous system.

Reactions of Ethanol:

1. Reaction with sodium: 2C₂H₅OH + 2Na → 2C₂H₅ONa + H₂
2. Oxidation to ethanoic acid: C₂H₅OH → CH₃COOH

Ethanoic Acid (CH₃COOH)

• Physical properties: Colourless liquid, sour taste, vinegar contains 5-8% ethanoic acid, melting point 290 K (glacial acetic acid), which means it can freeze during cold weather.
• Uses:
  
  • As a preservative in pickles.
  • In the manufacture of plastics, dyes, and perfumes.

Reactions of Ethanoic Acid:

1. Reaction with base (neutralization): CH₃COOH + NaOH → CH₃COONa + H₂O
2. Reaction with carbonates and bicarbonates: CH₃COOH + NaHCO₃ → CH₃COONa + CO₂ + H₂O
3. Esterification: CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O (in presence of acid catalyst)

Soaps and Detergents – Micelle Formation Explained

Soaps are sodium or potassium salts of long-chain carboxylic acids. They are made by heating animal fats or vegetable oils with sodium hydroxide (saponification).

Action of Soap: Soap molecules have two ends - hydrophobic tail (non-polar, attracted to oil) and hydrophilic head (polar, attracted to water). In water, they form micelles that trap oily dirt inside, allowing it to be washed away.

Detergents: Detergents are similar to soaps but made from petrochemicals. They work even in hard water because they do not form scum.

For better practice, check out the CBSE Class 10 Science Sample Papers

Conclusion & Key Takeaways

Carbon and its compounds form the foundation of organic chemistry and play a vital role in our daily lives. Their ability to form strong covalent bonds and long chains makes them incredibly versatile, creating everything from simple fuels to complex molecules like DNA.

Through class 10 chemistry chapter 4 notes, we explored how carbon bonds, its types of compounds, functional groups, and various reactions such as combustion, oxidation, addition, and substitution. 

We also learned about important substances like ethanol and ethanoic acid, and how products like soaps and detergents work.

In short, carbon is more than just an element; it’s the building block of life and industry. Mastering this topic opens the door to deeper studies in chemistry and real-world innovations.

FAQs

Q1. What are functional groups?

Ans. Functional groups are specific groups of atoms that determine the chemical properties of organic compounds. Examples include –OH (alcohol), –COOH (carboxylic acid) and –CHO (aldehyde).

Q2. What is a homologous series?

Ans. A homologous series is a group of organic compounds with the same functional group and similar chemical properties, where each successive member differs by a –CH₂– unit.

Q3. What are soaps and detergents?

Ans. Soaps are sodium or potassium salts of fatty acids used for cleaning, while detergents are synthetic cleaning agents that work even in hard water.

Q4. What is the difference between soap and detergent?

Ans. Soaps do not lather well in hard water due to scum formation, whereas detergents can lather well even in hard water.

Q5. Why are carbon compounds mainly covalent in nature?

Ans. Carbon compounds are covalent because carbon shares electrons to complete its octet instead of losing or gaining electrons.

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