Halogenoalkanes reactions

HideShow resource information
  • Created by: Zohar
  • Created on: 15-03-15 20:58
Halogenoalkane reaction with KOH (aq)
SN1/2 reaction forming alcohols - hydrolysis
1 of 10
halogenoalkane reaction with KOH (ethanol) when boiled under reflux
Elimination reaction forming alkene +Br- + H2O with E2 mechanism (OH- attacks an H on the halogenoalkane)
2 of 10
Rate of reaction with halogenoalkanes
C-I > C-Br > C-Cl bc decreasing bond length = stronger bond = more E to break
3 of 10
reaction of haloalkane with NaOH (aq)
forms alcohol + Br-, must be boiled under reflux
4 of 10
reaction of haloalkane with NH3 (eth) when boiled under reflux
C2H5Br + 2NH3 -> HBr + C2H5NH2 (aminoethane) then NH3 +HBr -> NH4Br
5 of 10
what are nucleophiles that react with haloalkanes
OH- , CN- and NH3 (lone electron pair)
6 of 10
test for halogenoalkanes
add to NaOH (aq) & warm -> cool -> add dilute nitric acid -> add silver nitrate solution. Results: RCl is white ppt (soluble in dilute NH3 soln), RBr is cream ppt (insoluble in ", soluble in conc NH3), RI is yellow ppt (insoluble in" &")
7 of 10
uses of haloalkanes
refrigerants: chemically inert CFCs which break down ozone (become Cl radicals under UV). Fire retardants bc v chemically inert- non-flammable. Herbicides &pesticides which stay in environment for ages
8 of 10
why use 50% H2SO4 when preparing CH3Br?
to prevent the product HBr being oxidised by the acid to Br2
9 of 10
What is oxidation?
Addition of oxygen or removal of hydrogen
10 of 10

Other cards in this set

Card 2

Front

halogenoalkane reaction with KOH (ethanol) when boiled under reflux

Back

Elimination reaction forming alkene +Br- + H2O with E2 mechanism (OH- attacks an H on the halogenoalkane)

Card 3

Front

Rate of reaction with halogenoalkanes

Back

Preview of the front of card 3

Card 4

Front

reaction of haloalkane with NaOH (aq)

Back

Preview of the front of card 4

Card 5

Front

reaction of haloalkane with NH3 (eth) when boiled under reflux

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Reactions resources »