Halogenoalkanes Flashcards
Halogenoalkanes:
What’s meant by Halogenoalkanes?
When H in Alkanes are replaced w Halogens
Halogenoalkanes:
What are Halogenoalkanes reacted with?
Nucleophiles
Halogenoalkanes:
What are Nucleophiles?
Species that donate electron pairs
Halogenoalkanes:
What charge are Nucleophiles?
δ- or -
Halogenoalkanes: Primary,Secondary & Tertiary Structures
What are Primary Halogenoalkanes?
Carbon-cation is found by breaking Halogen away from C
Carbon-cation is attached to 1 Alkyl Group & 2 Hydrogens
Halogenoalkanes: Primary,Secondary & Tertiary Structures
What are Secondary Halogenoalkanes?
Carbon-cation is found by breaking Halogen away from C
Carbon-cation is attached to 2 Alkyl Groups & 1 Hydrogen
Halogenoalkanes: Primary,Secondary & Tertiary Structures
What are Tertiary Halogenoalkanes?
Carbon-cation is found by breaking Halogen away from C
Carbon-cation is attached to 3 Alkyl Groups & no Hydrogens
Halogenoalkanes: Primary,Secondary & Tertiary Structures
Which Halogenoalkanane Structure is most stable?
Tertiary
Halogenoalkanes: Bond Enthalpy
How do you break Halogenoalkane?
Break halogen away from Carbon chain attaching the chain to something else
Halogenoalkanes: Bond Enthalpy in terms of IMFs
What’s the trend of Halogenoalkanes in terms of Bond Enthalpy & IMFs?
- Down G7, atomic radius increases
↳ more electrons
↳ more IMFs
↳ higher mp/bp : more energy needed to break it down
Hence C-I has the highest mp/bp
↳ hardest to break
Halogenoalkanes: Bond Enthalpy in terms of NC
What’s the trend of Halogenoalkanes in terms of Bond Enthalpy & NC?
- Down G7, atomic radius increases
↳ outer e- = further away shielded by inner e-
↳ ionise quicker : nuclear charge is reduced
↳ lower mp/bp : less energy needed to break it down
Hence C-I has the lowerst mp/bp
↳ easiest to break
Halogenoalkanes: Bond Enthalpy IMFs VS NC
Which one takes priority?
Nuclear Charge
Halogenoalkanes: Bond Enthalpy IMFs VS NC
Why does NC take priority?
Weaker Carbon-Hydrogen (e.g C-I) bonds break first
↳ they react the fastest
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What’s formed when a Halogenoalkane is hydrolysed w water?
An alcohol
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What’s the equation for this reaction?
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What type of Fission occurs?
Heterolytic Fission
↳ bond breaks unevenly, an atom receives both radicals forming 2 ions
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What’s the Nucleophile in this reaction?
Water
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
How would you identify the Halide formed in this reaction?
Add Silver Nitrate into solution
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
Why would you add Silver Nitrate to the solution?
Silver Halide precipitate is formed at different rates
↳ undissolved solid
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
How would you identify the Halide?
Identify colour change
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What colour is the AgCl Precipitate?
White
Halogenoalkanes: Halogenoalkane Hydrolysis using Water
What colour is the AgBr Precipitate?
Cream