12.2 Mechanism For Halogenation Of Alkanes Flashcards
What is a sigma bond?
An overlap of 2 orbitals between atoms
What is homolytic fission?
Where a single bond breaks to form 2 radicals
What is a radical?
A molecule with an unpaired electron
What is hetrolytic fission?
Where a single covalent bond breaks and one atom takes both electrons
Why is hetrolytic fission more common in a polarised bond?
The electrons are already being pulled to one side
Do alkenes undergo homolytic or hetrolytic fission?
Homolytic because they are non polar
What is the first step of bromation and what happens in it?
Initiation
Where Br2 goes to 2 bromine radicals under UV light
What is the second step of bromation and what is it called?
Propagation
Reacting a hydrocarbon for example like methane with your bromine radical to make a methane radical and HBr
Your methane radical then reacts with Br2 to make a Bromomethane and a Bromine radical
What is the last step in bromation and what is it called?
Termination
Two bromine radicals make Br2
Methane radical + Methane radical= Ethane
Methane radical +Br radical= bromomethane
What is the limit to bromanation?
It can go on for ever and be very messy
What is the equation for complete combustion and incomplete?
Hydrocarbon+ O2 = H20 + CO2
Hydrocarbon+ O2 = H20 + CO
