introduction to organic chemistry (3.3.1)

the actual number of atoms of each element in a compound eg. ethene - C2H4

the simplest whole number ratio of atoms of each element in a compound eg. butane - C2H5

how the atoms in a molecule are arranged, but not all the bonds are shown eg. ethene - CH2=CH2

how the atoms in a molecule are arranged with all of the bonds shown eg. butanoic acid

when only the carbon-carbon bonds are shown (using lines - each point represents a C atom), along with bonds to and atom labels for any atoms that aren’t C or H eg. butanoic acid

the simplest algebraic formula for a member of a homologous series eg. alkanes - CnH2n+2

a group of atoms responsible for the chemical reactions of a particular compound eg. carboxylic acids - COOH

a series of organic compounds with the same functional group, but each successive member has an additional -CH2

they have the same general formula and functional group, similar chemical properties and a gradual trend in physical properties

• find the longest continuous chain of C atoms and apply a prefix based on the number of C atoms (meth-, eth-, prop- etc) • if there is a ring of C atoms, add cyclo as well • if there are any C=C bonds, use the suffix -ene, if not use -ane • number the position of the carbon atoms from one end of the chain, giving C=C bonds, functional groups or side chains the lowest possible number • if there are multiple side chains or functional groups, arrange the prefixes alphabetically ie. bromo- comes before chloro- • if there is more than one of the same group, use di- for 2, tri- for 3, tetra- for 4 etc • give the position of every group, numbering from end of the C chain so the lowest possible numbers are used (if there is a C=C bond, start from the end which gives these 2 C atoms the lowest possible number) • separate numbers and letters with - , and numbers with ,

methyl groups (2 - one on each side of the C atom)

the CH3 might not be a methyl group - it may be another C atom which is part of the main chain but has been shown as a branch (so don’t add methyl group to name)

2-methylhexane

1,2-dibromo-1-chlorobutane

2-bromo-4-methylpent-2-ene

2-methylhex-3-ene

when two compounds have the same molecular formula but a different structural formula chain isomer, position isomer, functional group isomer

molecules with the same molecular formula but a different arrangement of carbon atoms in the main chain eg. pentane and dimethylpropane

molecules with the same molecular formula but the functional group in a different position in the molecule eg. pent-1-ene and pent-2-ene

molecules with the same molecular formula but different functional groups eg. cyclopropane and propene

when two compounds have the same molecular formula and structural formula, but a different arrangement of atoms and bonds

a type of stereoisomerism which occurs as a result of restricted rotation about a planar carbon-carbon double bond

E = entgegen (german for opposite) they are when the priority groups are next to each other on the same side of the molecule

Z = zusammen (german for together) they are when the priority groups are opposite each other on different sides of the molecule