Organic Chemistry I - AQA Chemistry A-level

Chain isomers

Isomers resulting from branching in the carbon chain

Displayed formula

Structural isomer showing all bonds between atoms

Empirical formula

Smallest whole number ratio of atoms in a compound

E-Z isomerism

Stereoisomerism due to restricted rotation around a double bond

Free-radical

Molecule with an unpaired valence electron

Functional group

Atoms responsible for characteristic reactions in a compound

Functional group isomers

Isomers with different functional groups

General formula

Empirical formula representing an entire class of compounds

Homologous series

Compounds with the same functional group and properties

Molecular formula

Total number of atoms of each element in a compound

Position isomer

Isomers with the same carbon backbone but different group positions

Skeletal formula

Diagram showing bonds between atoms with assumed hydrogens

Stereoisomerism

Isomerism when double bonded carbons have different groups

Structural formula

Formula showing atom arrangement but not all bonds

Structural isomerism

Compounds with the same molecular but different structural formula

Catalytic converter

Device reducing emissions in a car using a catalyst

Catalytic cracking

Cracking at high temperature with a zeolite catalyst

Combustion of alkanes

Process releasing energy by oxidising carbon and hydrogen

Cracking

Process breaking C-C bonds in alkanes to produce shorter chains

Crude oil

Finite resource from ancient biomass, mainly hydrocarbons

Fractional distillation

Separating substances by boiling points, e.g., crude oil fractions

Hydrocarbons

Compounds of carbon and hydrogen only

Saturated

Organic compounds with single C-C bonds

Thermal cracking

High temp cracking producing alkenes

Chlorofluorocarbons

CFCs containing carbon, chlorine, and fluorine

Electrophile

Electron acceptor in organic reactions

Elimination

Reaction forming a C=C bond by losing atoms

Free radicals

Species with unpaired electrons

Free radical substitution

UV light reaction forming halogenoalkanes

Nucleophile

Donates electron pair to form covalent bond

Nucleophilic substitution

Electron pair donor replacing a species

Ozone

Forms naturally, absorbs UV radiation

Ozone depletion

Chlorine catalyses ozone decomposition

Polar bond

Unequally distributed electron covalent bond

Addition polymer

Polymer from addition polymerisation of C=C monomers

Addition polymerisation

Formation of addition polymers from short chain monomers

Alkenes

Unsaturated hydrocarbons with C=C bond

Carbocation

Carbon atom with a positive charge

Major/minor products

Products from electrophilic addition based on stability

Monomer

Short chain molecule forming a polymer

Plasticiser

Chemical added to polymers for flexibility

Polymer

Long-chain molecules from small monomers

Repeat unit

Part of a polymer forming the complete polymer chain

Unsaturated

Organic compounds with at least one C=C bond

Alcohols

Contain -OH functional group; e.g., methanol, ethanol

Biofuel

Fuel derived from living matter, e.g., ethanol

Carbon-neutral fuel

Fuel with no net increase in atmospheric CO2

Distillation

Separating liquids by boiling point differences

Fermentation of glucose

Industrial process producing ethanol from glucose

Hydration of alkenes

Process to produce alcohols from alkenes

Oxidation of alcohols

Alcohols react with acidified potassium dichromate

Aldehyde

Molecule with C=O group forming silver mirror with Tollens’ reagent

Alkene

Molecule with C=C group decolourising bromine water

Carboxylic Acid

Molecule with COOH group reacting with sodium carbonate

Functional Group

Atoms responsible for characteristic compound reactions

Infrared Spectroscopy

Technique to identify bonds and functional groups in molecules

Mass Spectrometry

Identifies compounds and determines molecular mass

Molecular Formula

Total atoms of each element in a compound

Relative atomic mass

Average mass of an element's atom compared to carbon-12

Relative molecular mass

Average mass of one molecule compared to carbon-12

Wavenumber

Represents energy and frequency of absorbed IR radiation