Halogenalkanes Flashcards
why are halogenalkanes reactive as you go done the group 7?
polarity and elecrtongeativity decreases. As they are slightly postitive or electron deficint, theres more chance of a nucleophile attacking it and as they are more elecrtonegativive than carbon will pull elctron into covalent bond.
What is a nucleophile (always alkanes)
an lone pair of elecrton donor to form covalent bond
What is an eletrophile ( always alkenes)
species that is attracted to a high electron denisty
Examples of nucleophiles
Nh3 OH, CN
primary formula of halogenalakne
secondary
teritary
RX
R2CHX
R3CHX
why is ethanol used in hydrolyiss
solvent to allow halgenalkane and silver nitrate to mix as they form seperate layers
Describe results of Iodine bromine and chlorine
iodine was cream yellow, bromine was misty yellow and chlorine was clear
Why is it that as you go down the group , hydrolyses occurs faster
As you go down the group halide ion gets larger so leads to weaker bond.
C-I has the weaker bond enthaply so breaks easiest so percipate is formed first
why dont you use fluoroalknes in hydorlysis
this is because bond is much stronegr than any one else so heat from equipemnt isnt strong enough to break bond.
Decribe OH reaction with halogen alkane
NaOH is used, alkane is formed as halogen is replaced with OH group and halogen is on its own
Decribe NH3 with halogenalkane and draw
Primary amine is formed as NH3 will replace one carbon. excess NH3 is needed as a base so gives elecrton to H+ stablising charge of N and ammonium halogen is produced
decrbe CN reaction with halogenalkane
CN replaces halgen and nirtile is made whereby an CN is the extra carbon added and Cl is on its own
Primary of an achol structural formula
secondary
terianary
RCH2OH
R2CHOH
R3CHOH
