4.2.2 haloalkanes
- Created by: avocado05
- Created on: 06-03-22 19:04
View mindmap
- haloalkanes
- definitions
- nuleophile
- electron pair donor
- curly arrow
- shows the movement of electron pairs
- heterolytic fission
- breaking of a covalent bond where one atom gains both shared electrons forming anion and cation
- nuleophile
- reactivity
- haloalkanes become more reactive as you go down the group and hydrolyse the fastest
- down group, bond strength becomes weaker since lower bond enthalpy
- requires less energy to break bonds
- down group, bond strength becomes weaker since lower bond enthalpy
- haloalkanes become more reactive as you go down the group and hydrolyse the fastest
- nucleophilic substitution
- can be with any nucleophile such as OH-
- heterolytic
- both electrons move to halogen
- new bond formed between C and OH-
- must know mechanism
- new bond formed between C and OH-
- both electrons move to halogen
- nucleophile attacks d+ carbon and replaces halogen
- conditions
- react with ethanoic aqueous solution of warm NaOH
- under reflux
- react with ethanoic aqueous solution of warm NaOH
- reaction with water
- conditions
- heat with water under reflux
- water weak nucleophile so reaction slower
- oxygen only carries partial -ve charge in water, but full -ve charge in OH-
- RX + H2O = ROH + H+ + X-
- conditions
- test for reactivity
- aqueous silver nitrate
- iodide = yellow ppt forms fastest
- bromide = cream ppt forms second
- chloride = white ppt forms slowest
- Ag+ +X- = AgX
- aqueous silver nitrate
- environment
- ozone
- formed naturally when O2 molecule broken down into 2 free radicals by UV which then attack other oxygen molecules forming ozone
- homolytic fission
- formed naturally when O2 molecule broken down into 2 free radicals by UV which then attack other oxygen molecules forming ozone
- CFCs
- uses: refrigerants, flame retardants, dry - cleaning solvents
- UV provides sufficient energy to break C-hal bond by homolytic fission
- C-Cl bond has lowest bond enthalpy so breaks
- photodissociation
- C-Cl bond has lowest bond enthalpy so breaks
- stable, volatile, non-flammable
- ozone
- definitions
- Untitled
Comments
No comments have yet been made