O1: 13 Halogenoalkanes Flashcards
What do halogenoalkanes contain?
Polar bonds.
What is an electrophile?
Electron pair acceptor.
What is a nucleophile?
Electron pair donor.
Name and outline the mechanism and conditions of the reaction between a halogenoalkane and NaOH. What does the OH- act as?
Nucleophilic substitution.
Aqueous, warm NaOH.
OH- acts as a nucleophile.
See sheet.
Name and outline the mechanism and conditions of the reaction between a halogenoalkane and KCN.
Nucleophilic substitution.
Ethanolic, warm KCN.
See sheet.
Name and outline the mechanism and conditions of the reaction between a halogenoalkane and NH3.
Nucleophilic substitution.
Excess concentrated NH3.
See sheet.
Name and outline the mechanism and conditions of the reaction between a halogenoalkane and KOH. What does the OH- act as?
Elimination.
Ethanolic, hot KOH.
OH- acts as a base.
See sheet.
Why does the carbon-halogen bond enthalpy influence the rate of reaction?
A stronger bond takes more time and energy to break so the rate of reaction is slower.
Why is ozone beneficial?
It absorbs ultraviolet radiation.
How are chlorine free radicals formed in the upper atmosphere?
Ultraviolet radiation causes C-Cl bonds to break in CFCs.
What do chlorine free radicals do in the atmosphere?
They catalyse the decomposition of ozone and contribute to the hole in the ozone layer.
What are the equations of chlorine radicals reacting with ozone molecules?
Cl. + O3 -> .ClO + O2
.ClO + O3 -> .Cl + 2O2
What is the overall equation for the decomposition of ozone?
2O3 -> 3O2
