HALOALKANES Flashcards
(15 cards)
What are haloalkanes?
Saturated organic compounds that
contain carbon atoms and at least one
halogen atoms
Are halogenoalkanes soluble in water?
Insoluble as C-H bonds are non-polar,
not compensated for enough by C-X
bond polarity
Do halogenoalkanes have a polar bond? Why?
Yes polar, as halogen has a higher
electronegativity than C ( halogen is δ-, carbon is
δ+)
What type intermolecular forces do they have? Why?
Permanent dipole-dipole and Londonforces of attraction
C-X bond polarity creates permanent
dipoles
When would they have higher boiling points?
Increase Carbon chain length
Halogen further down group 7
How would the mass of a haloalkane compare with the mass of an
alkane of the same chain length?
Greater as mass of halogen > mass of H
What is the most important factor in determining halogen reactivity?
bond enthalpy of c-halogen
What would bond polarity suggest the order of reactivity would be?
C-F would be most reactive as most polar bond
What would bond enthalpies suggest the order of reactivity would
be?
C-I would be most reactive as lowest
bond enthalpy
define nucleophile
electron pair donor
give 3 examples of nucleophiles
OH-
CN-
NH3
What is nucleophilic substitution?
A reaction where a nucleophile donates a lone pair of electrons to δ+ C atom, δ− atom leaves molecule (replaced by nucleophiles)
What are CFCs?
Chlorine-fluoro-carbons - haloalkanes
containing C, F and Cl only (no H)
What is the problem with CFCs?
Although unreactive under normal
conditions, they catalyse the breakdown
of ozone in the atmosphere via free
radical substitution
Write an equation for the overall decomposition of ozone into
oxygen (O2)
2O3→ 3O2
