carbon and its compounds

• Carbon is an element of immense significance to us in both its elemental form and in the combined form
• Food, clothes, medicines, books, and many other things are based on the versatile element carbon
• All living structures are carbon-based
• The earth's crust has only 0.02% carbon in the form of minerals like carbonates, hydrogen-carbonates, coal, and petroleum
• The atmosphere has 0.03% of carbon dioxide
• Despite the small amount of carbon available in nature, the importance of carbon is immense
• Carbon forms covalent bonds by sharing electrons with other atoms
• Carbon has four electrons in its outermost shell and needs to gain or lose four electrons to attain noble gas configuration
• Carbon overcomes this by sharing its valence electrons with other atoms of carbon or with atoms of other elements
• Compounds of carbon are largely non-conductors of electricity
• Carbon compounds have low melting and boiling points compared to ionic compounds
• Carbon compounds are poor conductors of electricity
• Carbon forms covalent bonds with other atoms, leading to strong bonds within the molecule but weak intermolecular forces
• Diamond and graphite are allotropes of carbon with different physical properties
• Diamond is the hardest substance known while graphite is a good conductor of electricity
• Fullerenes are another class of carbon allotropes
• Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large molecules (catenation)
• Compounds of carbon may have long chains, branched chains, or carbon atoms arranged in rings
• Carbon atoms may be linked by single, double, or triple bonds
• Compounds of carbon linked by single bonds are saturated compounds, while those with double or triple bonds are unsaturated compounds
• Carbon compounds are very reactive
• The carbon-carbon bond is very strong and stable
• Carbon has a valency of four, capable of bonding with four other atoms of carbon or atoms of some other mono-valent element
• Compounds of carbon are formed with oxygen, hydrogen, nitrogen, sulphur, chlorine, and many other elements, giving rise to compounds with specific properties
• Bonds that carbon forms with most other elements are very strong, making these compounds exceptionally stable
• Carbon compounds can be extracted from natural substances
• Organic compounds were initially thought to only be formed within a living system, but this was disproved by Friedrich Wöhler in 1828
• Saturated carbon compounds have single bonds between carbon atoms and are not very reactive
• Example: Methane (CH4), Ethane (C2H6), Propane (C3H8)
• Unsaturated carbon compounds have double or triple bonds between carbon atoms and are more reactive than saturated compounds
• Example: Ethene (C2H4), Ethyne (C2H2)
• Chains of carbon atoms can contain many more carbon atoms
• Carbon compounds can form chains, branches, or rings
• Compounds with identical molecular formula but different structures are called structural isomers
• Compounds can have carbon atoms arranged in the form of a ring, such as cyclohexane (C6H12)
• Hydrocarbons contain only carbon and hydrogen
• Saturated hydrocarbons are called alkanes
• Unsaturated hydrocarbons with double bonds are called alkenes
• Unsaturated hydrocarbons with triple bonds are called alkynes
• Carbon forms bonds with elements such as halogens, oxygen, nitrogen, and sulphur