year 1 organic chemistry

• Chain isomers


  Isomers that occur due to the branching in the carbon chain
• Displayed formula


  A type of structural isomer that shows all the bonds between every atom in the compound

  
• Empirical formula


  The smallest whole number ratio of atoms of each element in a compound
• 1. Z isomerism


  A type of stereoisomerism that occurs due to the restricted rotation around the carbon double bond. This results in two different groups on one end of the bond and two different groups on the other end. If the highest priority groups for each carbon are found on the same side of the molecule, then it is the Z-isomer. If the highest priority groups for each carbon are found on opposite sides of the molecule, then it is the E-isomer
• Free-radical


  An uncharged molecule or atom with an unpaired valence electron
• Functional group


  The group of atoms responsible for the characteristic reactions of a particular compound
• Functional group isomers


  Isomers that contain different functional groups. This means they belong to different homologous series
• General formula


  A type of empirical formula that represents the composition of any member of an entire class of compounds
• Homologous series


  A series of compounds with the same functional group and similar chemical properties
• Molecular formula


  Total number of atoms of each element in the compound
• Position isomer


  Isomers where the carbon backbone of the isomers are the same but the important groups are at different positions on the backbone
• Skeletal formula


  A diagram representation of an organic compound in which lines represent bonds between atoms and atoms are represented by their symbol. Hydrogens are assumed to be at the end of the line if no other atomic symbol is present
• Stereoisomerism


  Occurs when two double bonded carbon atoms each have two different atoms or groups attached to them. Includes E/Z isomerism. This is a consequence of a restricted rotation around the C=C double bond
• Structural formula


  A formula which shows the arrangement of atoms in the molecule of a compound but does not show all the bonds between them

  
• Structural isomerism


  Structural isomers are compounds which have the same molecular formula but a different structural formula
• Catalytic converter


  A device fitted in a car to reduce the amount of emissions from an internal combustion engine. They use expensive metals like platinum and rhodium as the heterogeneous catalyst. The catalyst is mounted on a ceramic honeycomb to maximise the surface area
• Catalytic cracking


  A type of cracking that takes place at a slight pressure, high temperature and in the presence of a zeolite catalyst and is used mainly to produce motor fuels and aromatic hydrocarbons
• Combustion of alkanes - releases energy. During combustion, the carbon and hydrogen in the fuels are oxidised. Alkanes can undergo complete or incomplete combustion. Water and carbon dioxide are the only products of the complete combustion, whereas carbon monoxide and carbon particulates can be produced in incomplete combustion
• Cracking


  A process which involves breaking C-C bonds in alkanes to produce shorter chained alkanes and alkenes
• Crude oil


  A finite resource found in rocks. It is the remains of an ancient biomass consisting mainly of plankton that was buried in mud. Most of the compounds in crude oil are hydrocarbons
• Fractional distillation


  A method of separating a mixture of substances according to their different boiling points. Commonly used to separate crude oil into different fractions
• Hydrocarbons


  Compounds made up of carbon and hydrogen atoms only
• Saturated


  Organic compounds are saturated if all the carbon-carbon bonds are single C-C bonds. Alkanes are saturated hydrocarbons
• Thermal cracking


  A type of cracking that takes place at high pressure and high temperature and produces a high percentage of alkenes
• Chlorofluorocarbons- also known as CFCs, are chemicals containing carbon, chlorine and fluorine atoms. CFCs contribute to ozone depletion so they are banned for use in refrigerants and solvents
• Electrophile


  Electron pair acceptor in an organic mechanism. Attracted to areas with a lot of electrons/high negative charge
• Elimination


  A reaction in which a molecule loses atoms or groups of atoms to form a C=C bond
• Free radicals


  A species with an unpaired electron. Represented in mechanisms by a single dot
• Free radical substitution


  A photochemical reaction between halogens and alkanes to form halogenoalkanes. The reaction requires UV light and involves three stages: initiation, propagation and termination. Initiation initially creates a radical species. Propagation involves a series of chain reactions where free radicals bond to molecules to form new free radicals. Termination involves the reaction of free radicals with other free radicals to form new molecules
• Nucleophile


  An atom or molecule that donates an electron pair to form a covalent bond. Attracted to electron-deficient areas
• Nucleophilic substitution


  The reaction of an electron pair donor (the nucleophile) with an electron pair acceptor (the electrophile). Involves one species being replaced with another species
• Ozone


  Ozone is formed naturally in the upper atmosphere. It is beneficial because it absorbs ultraviolet radiation and this prevents harmful radiation reaching the earth. Ozone is formed by the following reaction: 3O2 (+ uv light) → 2O3
• Ozone depletion


  Chlorine atoms catalyse the decomposition of ozone and contribute to the hole in the ozone layer
• Polar bond


  A covalent bond where the electrons are not distributed equally. This causes the molecule to have a slight dipole so that one end is slightly positively charged and the other end is slightly negatively charged. Halogenoalkanes contain polar bonds due to the difference in electronegativity between the halogen atom and carbon atom
• Addition polymer


  A polymer formed by addition polymerisation. Formed from monomers with C=C bonds
• Addition polymerisation


  The process by which addition polymers are formed. Lots of short chain monomers (alkenes) join together to form a long chain polymer by the 'opening up' of all the double carbon bonds
• Alkenes


  Alkenes are hydrocarbons with a double bond between two of the carbon atoms in their chain, causing them to be unsaturated. They have the general formula CnH2n

  
• Carbocation


  A carbon atom bearing a positive charge
• Major/minor products


  Major and minor products are formed from electrophilic addition due to the relative stabilities of the primary/secondary/tertiary carbocation intermediates. The major product is formed from the most stable intermediate and the minor product is formed from the least stable intermediate
• Monomer


  A short chain molecule that when bonded to other monomers forms a polymer