Class 10 Science Notes: Carbon and Its Compounds PDF

Class 10 Science Notes: Carbon and Its Compounds Introduction to Carbon - Unique Nature of Carbon: - Tetravalency: Carbon has 4 valence electrons, enabling it to form four covalent bonds. - Catenation: Carbon can form long chains by bonding with other carbon atoms. - Forms a variety of compo...

Class 10 Science Notes: Carbon and Its Compounds Introduction to Carbon - Unique Nature of Carbon: - Tetravalency: Carbon has 4 valence electrons, enabling it to form four covalent bonds. - Catenation: Carbon can form long chains by bonding with other carbon atoms. - Forms a variety of compounds: Straight chains, branched chains, and rings. - Bonds with hydrogen, oxygen, nitrogen, sulfur, and halogens. Covalent Bonding in Carbon - Covalent Bond: Formed by the sharing of electrons. - Example: Methane (CH4): Carbon shares its 4 electrons with 4 hydrogen atoms. Allotropes of Carbon 1. Diamond: Hardest substance, used in cutting tools. 2. Graphite: Conducts electricity, used as a lubricant. 3. Fullerenes: Spherical molecules (e.g., C60). Versatile Nature of Carbon - Carbon forms single, double, and triple bonds (e.g., ethane, ethene, ethyne). - Forms compounds with a wide variety of properties and uses. Hydrocarbons - Definition: Compounds made up of only carbon and hydrogen. 1. Saturated Hydrocarbons (Alkanes): Single bonds (e.g., Methane, CH4). 2. Unsaturated Hydrocarbons:  - Alkenes: Double bonds (e.g., Ethene, C2H4). - Alkynes: Triple bonds (e.g., Ethyne, C2H2). Homologous Series - A series of organic compounds with the same functional group and similar chemical properties. - Characteristics: - Same general formula. - Gradation in physical properties. - Difference of -CH2 group between consecutive members. Functional Groups - Groups of atoms that determine the chemical properties of a compound. - Alcohol (-OH): Example: Ethanol (C2H5OH). - Aldehyde (-CHO): Example: Ethanal (CH3CHO). - Ketone (-CO-): Example: Propanone (CH3COCH3). - Carboxylic Acid (-COOH): Example: Ethanoic Acid (CH3COOH). Nomenclature of Organic Compounds - Rules: 1. Identify the longest carbon chain. 2. Number the chain to give the lowest position to functional groups. 3. Name substituents with their positions. Chemical Properties of Carbon Compounds 1. Combustion: Produces CO2 and H2O with the release of heat. - Example: CH4 + 2O2 -> CO2 + 2H2O. 2. Oxidation: Alcohols oxidize to acids using oxidizing agents (KMnO4, K2Cr2O7). 3. Addition Reactions: Unsaturated hydrocarbons add hydrogen in the presence of catalysts. 4. Substitution Reactions: Saturated hydrocarbons react with chlorine in the presence of sunlight. Ethanol and Ethanoic Acid 1. Ethanol (C2H5OH): - Colorless liquid, soluble in water. - Uses: Antiseptic, alcoholic beverages. - Reactions: - Combustion: C2H5OH + 3O2 -> 2CO2 + 3H2O. - Oxidation to ethanoic acid. 2. Ethanoic Acid (CH3COOH): - Sour taste, forms vinegar. - Reaction with bases: CH3COOH + NaOH -> CH3COONa + H2O. - Esterification: CH3COOH + C2H5OH -> CH3COOC2H5 + H2O. Soaps and Detergents 1. Soaps: Sodium or potassium salts of fatty acids. - Work by emulsifying grease and dirt in water. 2. Detergents: Synthetic compounds, effective even in hard water. Key Points to Remember - Carbon exhibits catenation and forms a diverse range of compounds. - Functional groups influence the properties of organic compounds. - Soaps and detergents have different applications based on water type.