alkanes Flashcards
what is a homologous series
a series of organic compounds with the same functional group but with each successive member differing by CH2
what is a functional group
a group of atoms responsible for the characteristic reactions of a compound
define aliphatic
contains no benzene rings (C5H6)
define alicyclic
contains no benzene rings but has have carbons joined in a ring
define aromatic
must contain one or more benzene ring C6H6
name the 7 common functional groups
alkane C-C alkene C=C haloalkane Cl Br I alcohol OH aldehyde -CHO ketone RCOR carboxylic acid COOH
what is a structural isomer
compounds with the same molecular formula but different structural formulas
what is the effect of increasing chain length on boiling point
as the number of carbon atoms in the chain increases, the boiling point increases - due to an increase in number of electrons so London forces are stronger which then require more energy to overcome
effect of branching on boiling point
more branching decreases the boiling point as there is less contact area between molecules so London forces are weaker and therefore require less energy to overcome
why are alkanes relativity unreactive
both c-c and c-h bonds are strong and have high bond enthalpy so in order to break the bonds to allow the reaction to occur a lot of energy must be supplied
define a radical
a species with an unpaired electron
what mechanism occurs between alkene and halogen
radical substitution
why is the reaction between halogen and alkene an example of a substitution reaction
hydrogen atoms in the alkene are replaced by halogen molecules
what 3 stages take place in radical substitution
- initiation
- propagation
- termination
what condition is needed for radical substitution to occur
UV light - provides enough energy to break halogen bond
