3.3 - Halogenoalkanes Flashcards
Conditions for Hydrolysis of Halogenoalkanes?
|> Aqueous
|> Room Temp
Reagents for Hydrolysis of Halogenoalkanes?
|> Aqueous Hydroxides e.g. NaOH, KOH
General Equation for the formation of Nitriles?
RX + CN⁻ |> RCN + X⁻
Why is Silver Iodide the fastest to form in reaction with Silver Nitrate Solution?
|> C-I bond is weakest
|> Eₐ is lower so there is a greater proportion of successful collisions in the same unit of time
Reactions for the Catalysed Breakdown of the Ozone Layer?
Cl⋅ + O₃ |> O₂ +ClO⋅
ClO⋅ + O₃ |> 2O₂ + Cl⋅
What test can be used to determine the rate of Hydrolysis?
Silver Nitrate Precipitate Test
What is the Nucleophile of a Hydrolysis reaction?
∶OH⁻
Overall reaction for the Breakdown of the Ozone Layer?
2O₃ |> 3O₂
What is the Base in an Elimination reaction?
∶OH⁻
Nucleophile or Base when forming Amines?
Both
What does the breakdown of CFCs form?
Chlorine Radicals
2 examples of Alternative organohalogen compounds?
CF₃ & C₄H₁₀
Why do Halogenoalkanes undergo Nucleophilic Substitution?
Contain a δ⁺ Carbon that attracts nucleophiles
Why is the Ozone layer Beneficial?
Absorbs UV radiation
Why can Silver Nitrate Solution not determine rate of Hydrolysis of 1-fluorobutane?
AgF is soluble
Some uses of Halogenoalkanes?
|> Refrigerants
|> Solvents
|> Pharmaceuticals
Why can’t water be used in formation of Nitriles?
Water has OH⁻ ions
Define: Elimination
A reaction in which an atom/(group of atoms) is removed from a reactant
Why is using CF₃ better than using CFCs?
|> no C-Cl bond
|> Breaks far above Ozone Layer
Define: Base
H⁺ acceptor
Define: Hydrolysis
Breaking of a Bond using Water
What does a Double-headed Curly Arrow show?
Movement of a pair of electrons
Role of ∶OH⁻ in an Elimination reaction?
Base
What is the Nucleophile in formation of Amines?
∶NH₃
Why is using C₄H₁₀ better than using CFCs?
|> no C-Cl bond
|> Breaks below Ozone Layer
What has been developed as a replacement for CFCs?
Alternative organohalogen compounds that do not contain Cl
Reagent when forming Amines?
Excess NH₃
What is formed when a halogenoalkane reacts with Excess ammonia?
Amines
Why are CFCs less of an issue today?
Ban Imposed
What can UV radiation cause?
Skin cancer
What does the reaction of a halogenoalkane with Cyanide increase?
Length of Carbon Chain
What do Chlorine Radicals Catalyse?
Breakdown of Ozone Layer
What carbon is a Nitrile group always named with?
No. 1
Why are Halogenoalkanes more reactive than Alkanes?
Contain a polar bond
In an Elimination reaction, what does a Halogenoalkane react to form?
Alkene
Nucleophile or Base in formation of Nitriles?
Nucleophile
Define: Nucleophile
Electron Pair Donor
What is the Base in the formation of Amines?
∶NH₃
What is formed when Halogenoalkanes react with KCN?
Nitriles
Why is there no Termination step of Chlorine radicals in the Ozone layer?
conc. of Cl⋅ is very low
General Formula of Halogenoalkanes?
CnH₂n₊₁X
General Equation for Hydrolysis?
NaOH(aq) + RCH₂X |> NaX + RCH₂OH
Reaction for the Breaking down of CFCs?
CF₂Cl₂ |> CF₂Cl⋅ + Cl⋅
General Equation for forming Amines?
RX + 2NH₃ |> RNH₂ + NH₄X
Nucleophile or Base in Hydrolysis reaction?
Nucleophile
What is the Nucleophile in formation of Nitriles?
∶CN⁻
Conditions for forming Amines from Halogenoalkanes?
Aqueous
Warm
Reagent for formation of Nitriles?
NaCN or KCN
Reagent for the Elimination of Halogenoalkanes?
NaOH
Conditions for formation of Nitriles?
Ethanol Solvent
Warm
Conditions for Elimination of Halogenoalkanes?
Ethanol Solvent
Reflux (boiling & recondensing w/ no gas escaping)
Reversible Reaction for Ozone formation?
O₃ < | > O₂ + O⋅⋅
fwd: UV light
reverse: infrared radiation
Nucleophile or Base in Elimination reaction of Halogenoalkanes?
Base
