Carbon & Covalent Compounds

Carbon & Its Compounds

• This topic covers various aspects of carbon compounds, including their formation, nomenclature, properties, and reactions.
• The notes highlight the importance of carbon's unique structure and its ability to form diverse compounds.
• Carbon forms covalent bonds due to its need to gain or lose four electrons.
• Carbon's ability to form long chains, branched chains, and rings are key to the creation of numerous carbon compounds.

Covalent Compounds

• Covalent compounds are formed when atoms share electrons to achieve a stable electron configuration.
• The sharing of electrons between atoms is called a covalent bond.
• Examples given in the presentation of covalent compounds are Cl₂, O₂, and N₂, along with their electron dot structures and types of covalent bonds (single, double, or triple).
• Covalent compounds are generally poor conductors of electricity due to the absence of charged particles.
• Covalent compounds usually have low melting and boiling points.

Properties of Covalent Compounds

• Covalent compounds are poor conductors of electricity due to the absence of charged particles (ions).
• They have generally relatively low melting and boiling points because they have weak intermolecular forces,
• The covalent bond itself is strong, despite the weak intermolecular forces.

Nomenclature - IUPAC

• IUPAC is the International Union of Pure and Applied Chemistry, used for naming chemical compounds according to universally accepted rules.
• Carbon atoms in a chain are numbered, and functional groups are incorporated into the name to define the exact chemical compound.
• Rules for naming different types of carbon compounds are included (e.g alkanes, alkenes, alkynes,).

Alkanes

• Alkanes are saturated hydrocarbons, meaning they only contain single bonds between carbon atoms.
• They have the general formula C_nH_2n+2.
• Examples given: Methane (CH₄), Ethane (C₂H₆), Propane (C₃H₈), Butane (C₄H₁₀) and Pentane (C₅H₁₂).
• These molecules exhibit a homologous series.

Alkenes

• Alkenes are unsaturated hydrocarbons containing at least one carbon-carbon double bond.
• They have the general formula C_nH_2n.
• Examples given: Ethene (C₂H₄), Propene(C₃H₆), Butene(C₄H₈).

Alkynes

• Alkynes are unsaturated hydrocarbons with a carbon-carbon triple bond.
• They have the general formula C_nH_2n-2.

Functional Groups

• Functional groups are specific groups of atoms within molecules that are responsible for most of the characteristic chemical reactions of those molecules.
• Types of functional groups include hydroxyl (-OH), carbonyl (C=O), and carboxyl (-COOH).
• The presence of functional groups dramatically changes the chemical properties and behavior of an organic compound.

Isomers

• Isomers are compounds with the same molecular formula but different structural arrangements of atoms.
• Example given of Butane (C₄H₁₀).
• Structural isomerism involves variations in how atoms are bonded together.

Heterocyclic Compounds

• No mention in the provided text

Homologous Series

• A homologous series is a series of organic compounds with the same functional group but with different numbers of carbon-carbon bonds between the atoms.
• Each member of a homologous series differs from the next member by one –CH₂– unit or two hydrogen atoms.

Reactions of Alcohols

• Alcohols undergo various reactions, including oxidation (to aldehydes or carboxylic acids) and dehydration (to alkenes).
• Alkaline KMnO4 and acidified K2Cr2O7 are oxidizing agents for alcohols.
• The reactions mentioned involved oxidation and dehydration, with examples including ethanol.

Reactions of Carboxylic Acids

• Carboxylic acids react with bases to produce salts and water, or with metal carbonates or bicarbonates to produce carbon dioxide, water and salts.
• Common observations in these reactions include: tests for CO₂ and reactions with bases

Benzene

• Benzene, a cyclic unsaturated hydrocarbon (C₆H₆). Key characteristic is alternating double (delocalized electrons).

Hard Water

• Hard water contains dissolved salts of calcium and magnesium.
• These salts prevent the formation of a lather when soap is used.
• Detergents are more effective in hard water.