intro to org chem

• Organic chemistry is the chemistry of carbon compounds.
• Carbon forms a vast number of compounds because it can form strong covalent bonds with itself, enabling it to form long chains of carbon atoms, branched chains or cycles, and hence an almost infinite variety of carbon compounds are known.
• Carbon always forms four covalent bonds which can be single, double or triple bonds.
• There is an almost infinite variety of chains, branches and rings able to form.
• A functional group is a specific atom or group of atoms which confer certain physical and chemical properties onto the molecule.
• Organic molecules are classified by the dominant functional group on the molecule.
• Organic compounds with the same functional group, but with each successive member different by CH2, are called a homologous series.
• Every time a carbon atom is added to the chain, two hydrogen atoms are also added, which is why the successive members differ by CH2.
• Hydrocarbons are compounds that are made up of carbon and hydrogen atoms only.
• Ethanol is not a hydrocarbon as the molecule also contains an oxygen atom and is not solely made up of carbon and hydrogen.
• Alkanes are the simplest hydrocarbons with no functional group, made up of carbon and hydrogen atoms bonded to each other with single covalent bonds.
• Alkanes are compounds made up of carbon and hydrogen atoms only and contain no functional group.
• Alkanes are the simplest hydrocarbons with no functional group and are made up of carbon and hydrogen atoms bonded to each other with single covalent bonds.
• The diagram below shows the arrangement of the π bond in sp, sp and sp hybridised carbon atoms.
• The two clouds of electrons in a π bond represent one bond consisting of two electrons (one from each orbital).
• Structural isomers are compounds that have the same molecular formula but different structural formulae, such as propene and cyclopropane.
• The π orbitals are formed from the sideway overlap of the atomic orbitals.
• Propyne has one planar centre around the carbon-carbon triple bond (linear) and one tetrahedral centre.
• There are three different types of structural isomerism: Chain isomerism, Positional isomerism, and Functional group isomerism.
• Propene has two trigonal planar centres around the carbon-carbon double bond and one tetrahedral centre.
• Planar molecules have all their atoms in the same plane, including linear, bent, trigonal planar and square planar.
• Ethyne is a planar molecule with one planar centre: the molecule is linear.
• The presence of an sp hybridised carbon can force the molecule to adopt a planar configuration (trigonal planar).
• Chain isomerism is when compounds have the same molecular formula, but their longest hydrocarbon chain is not the same, caused by branching.
• Ethene is a planar molecule with two trigonal planar centres around the carbon atoms.
• In triple bonds, there is an additional overlap of p orbital.
• π orbitals can be formed from the end-on overlap of p orbitals.
• The two lobes of the π bond lie in front of and behind the plane of the atoms in the molecule, maximising overlap of the p orbitals.
• Alkanes are the simplest hydrocarbons with no functional group and are compounds made up of carbon and hydrogen atoms only, containing no functional group.
• The adjacent numbers have a comma between them.
• Homologous series is a group of organic compounds that have the same functional group, the same general formula and the same chemical properties.
• An aliphatic compound is straight or branched-chain and also includes cyclic organic compounds that do not contain a benzene ring.
• Homolyticission is breaking a covalent bond in such a way that each atom takes an electron from the bond to form two radicals.
• The molecular formula shows the number and type of each atom in a molecule.
• Numbers are separated from words by a hyphen.
• Unsaturated hydrocarbons are hydrocarbons which contain carbon-carbon double or triple bonds.
• The empirical formula shows the simplest whole number ratio of the elements present in one molecule of the compound.
• Heterolyticission is breaking a covalent bond in such a way that the more electronegative atom takes both the electrons from the bond to form a negative ion and leaving behind a positive ion.
• If there are more than one of the same alkyl side-chain or functional groups, di- (for two), tri- (for three) or tetra- (for four) is added in front of its name.
• If there is more than one type of alkyl side-chain, they are listed in alphabetic order.