Radicals (not political ones!)
Professor El-Marsafy and Dr. Schwarz teamteaching with Frau Zengler at Lauterbach A.-v.-Humboldt-Highschool
In political life as well as in chemistry radicals are highly aggressive individuals:
Oxygen radicals attack the colour of black hair. Following a treatment by such radicals the person will be blonde.
Radicals are also pruduced by hard UV radiation at the border of our atmosphere.
Organic radicals formed in your skin under different influences from the environmet may harm your health. 
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Transforming hexane into 1bromo hexane - a radical substitution
.  . . . .
Reaction mechanism Radical Substitution ("advanced version")


Photo 1:
The organic substition type reaction between Hexane and Bromine (activated by light) is represented by the equation and by bead models using big blue beads  for R, black beads for
C atoms, white beads for H atoms and green beads for Br atoms.
The blue bead represents an R-group which is  C5H11-.


The radical substitution mechanism reaction is also represented by equations and visualized by bead models.
For molecule modelling on the advanced level  beads of the different colours and sizes are once once again used.  Beside that pairs of micro beads visualize the paired bonding electrons.
One micro bead and a piece of tubing are models of the unpaired electrons in radicals.


1. Start Reaction
Br2 molecules are cleaved releasing each two Br radicals.
 
 
 
 


2. Chain Reaction a
A hexane molecule reacts with a bromine radical attracting one hydrogen atom (with its electron) leaving an hexyl radical and producing an HBr molecule.
 
 
 
 
 


Chain Reaction b
A hexyl radical reacts with a bromine molecule producing a bromohexane molecule and releasing a bromine radical.
(This chain reaction goes on until all the bromine is consumed. Then the remaining hexylradicals undergo the terminating reaction).
 
 


3. Terminating Reaction
Two hexyl radicals join to produce a 12-C alkane.
 
 
 
 
 
 


Proton exchange reaction between HBr and water
 





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