BC and hydrocarbons : isomerism Flashcards
what is isomerism ?
a property that certain molecules within the same molecular formula show when their structures are different
what are isomers ?
organic compounds that have the same molecular formula but different arrangement of their atoms
give an example of isomer
cyclohexane and hexane
- they have the same molecular formula (C6H12) but their atoms are arranged differently
–> draw both and find in textbook :)
define structural isomers
compounds with the same molecular formula but different structural formulae
how may ways can the structural formulae change shape in terms of isomers ?
3 ways
what are the 3 types of structural isomers ?
- positional isomers
- functional group isomers
- chain isomers
what are the 2 types of stereoisomerism ?
- E/Z isomerism
- optical isomerism
what is a positional isomer ?
- a type of structural isomers, that has the functional group , substituent , double/triple bond located at different positions along the carbon chain
what is an example of a positional isomer that is an alkane ?
1-chlorobutane + 2-chlorobutane
why are these alkanes considered positional isomers ?
- the chlorine substituent is present at different positions of the carbon chain which as 4 carbons
what is an example of a positional isomer that is an alkene ?
but-1-ene + but-2-ene
why are these alkenes considered positional isomers ?
- the carbon to carbon double bond (C=C) is located at different position along the carbon-carbon chain which has 4 carbons
what is an example of a positional isomer that is an alcohol ?
butan-1-ol + butan-2-ol
why are these alcohol considered positional isomers ?
the hydroxyl functional group (OH-group) is at different positions along the carbon chain which has 4 carbons
what is a chain isomer ?
- a type of structural isomerism where the carbon chain length of the skeleton varies due to branching
what do chain isomers have the same of but different of ?
- the same molecular formula but different arrangements of the carbon chain
give an example of chain isomers - draw in skeletal formulae
- C5H12
find it notes
what is a functional group isomer ?
- a type of structural isomerism where only the functional group is different in the isomers and everything else will remain the same
what both have the general formula of CnH2n ?
alkenes + cycloalkanes
draw a skeletal formala for functionl groups with MF of CnH2n
find it notes - (propene + cyclopropane)
why are these functional groups with CnH2n general formula both functional groups isomers
- they both have the molecular formula of C3H6 and their functional groups are different so they are , functional group isomers
what both have the general formula of CnH2nO ?
aldeheydes and ketones
draw a skeletal formala for functionl groups with MF of CnH2nO
find in notes
propanal and propanone
why are these functional groups with CnH2nO general formula both functional groups isomers
both have the molecular formula of C3H6O and their functional groups are different so they are functional group isomers
