Pregunta 1
Pregunta
Free Radicals are formed from the [blank_start]homolytic[blank_end] fission of a [blank_start]covalent[blank_end] bond, often by UV light which provides enough energy to break the bond [blank_start]equally[blank_end]. This gives each 'half' one electron each. It is these unpaired electrons which make Free Radicals [blank_start]so reactive[blank_end].
Respuesta
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homolytic
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heterolytic
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covalent
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dative
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equally
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unequally
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so reactive
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very unreactive
Pregunta 2
Pregunta
Boiling point increases with size and length of a haloalkane because:
Respuesta
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there are more Van der Waal's Forces between molecules
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the molecules are heavier
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it will have further to go
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the bigger the molecule the less reactive it is
Pregunta 3
Pregunta
Look at this equation where methane and chlorine are combined in the presence of UV light to form 1-chloromethane and hydrochloric acid.
Select the correct Propogation reaction(s).
Pregunta 4
Pregunta
Look at this equation where methane and chlorine are combined in the presence of UV light to form 1-chloromethane and hydrochloric acid.
Select the correct Termination reaction(s).
Pregunta 5
Pregunta
Look at this reaction in which methane and chlorine are combined in the presence of UV light to form 1-chloromethane and hydrochloric acid.
Select the correct Initiation reaction(s).
Pregunta 6
Pregunta
Look at this reaction in which methane and chlorine are combined in the presence of UV light to form 1-chloromethane and hydrochloric acid.
The bond enthalpy of Cl-Cl is +243 kJ mol-1.
The bond enthalpy of C-H is +413 kJ mol-1.
In the Initiation reaction, the covalent bonds in the [blank_start]chlorine[blank_end] are more likely to be broken by the UV light because the [blank_start]Cl-Cl[blank_end] bond is much weaker than the [blank_start]C-H[blank_end] bond and [blank_start]easier[blank_end] to break.
Respuesta
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chlorine
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methane
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1-chloromethane
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hydrochloric acid
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Cl-Cl
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C-H
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C-H
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Cl-Cl
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easier
-
more difficult
Pregunta 7
Pregunta
Select all features of a Nucleophile.
Respuesta
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It has a lone pair of electrons
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It isn't an electron pair donor
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It always has a negative charge
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It is attracted to electron deficient (slightly positive) Carbon
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It has neutrons in its energy shells
Pregunta 8
Pregunta
What makes a good nucleophile?
Respuesta
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It possesses a charge
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Increased electronegativity
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Being a bad solvent
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Decreased steric hindrance
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Being able to remove neutrons
Pregunta 9
Pregunta
An atom/molecule/ion is only a nucleophile when is donates a pair of electons to an atom other than hydrogen, usually carbon.
Pregunta 10
Pregunta
Chlorofluorocarbons contain Hydrogen.
Pregunta 11
Pregunta
The alternatives to Chlorofluorocarbons are:
Respuesta
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Hydrocarbons
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Hydrofluorocarbons
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Bromofluorocarbons
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Flurocarbons
Pregunta 12
Pregunta
Chlorofluorocarbons are:
Respuesta
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reactive
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non-flammable
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toxic
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bad for the ozone layer
Pregunta 13
Pregunta
When you react a haloalkane with water, the products are:
Respuesta
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Hydrogen Halide
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an Alcohol
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a Halogen
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an Alkane
Pregunta 14
Pregunta
When you react a haloalkane with potassium/sodium cyanide under reflux in an aqueous alcoholic solution, the products are:
Respuesta
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Potassium/Sodium Halide
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a Nitrile
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Nitrogen gas
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a Halogen
Pregunta 15
Pregunta
When you react a haloalkane with an excess of ammonia in reflux under pressure, the products are:
Respuesta
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an Amine
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Ammonium Halide
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a Halogen
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Nitrogen gas
Pregunta 16
Pregunta
When Ammonia reacts in excess with a haloalkane, it acts as a _____ and then a _____:
Respuesta
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a Nucleophile with the haloalkane
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a Base with the hydrogen halide
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an Electrophile with the hydrocarbon
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an Acid with the hydrogen halide
Pregunta 17
Pregunta
In the elimination of haloalkanes with alcoholic potassium/sodium hydroxide, the products are:
Respuesta
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an Alkene
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Water
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Potassium/Sodium Halide
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a Halogen
Pregunta 18
Pregunta
This question concerns reacting Potassium/Sodium Hydroxide with a Haloalkane.
With Water as a solvent, the Hydroxide Ions act as [blank_start]a Nucleophile[blank_end]. The reaction is therefore is [blank_start]a Substitution[blank_end] and [blank_start]an Alcohol[blank_end] is formed. With Alcohol as a solvent, the Hydroxide Ions act as [blank_start]an Electrophile[blank_end]. The reaction is therefore is [blank_start]an Elimination[blank_end] and [blank_start]an Alkene[blank_end] is formed.
To favour Substitution, the temperature needs to be [blank_start]warm[blank_end] and the Potassium/Sodium Hydroxide needs to be [blank_start]dilute[blank_end] and [blank_start]aqueous[blank_end]. To favour Elimination, the temperature needs to be [blank_start]hot[blank_end] and the Potassium/Sodium Hydroxide needs to be [blank_start]concentrated[blank_end] and [blank_start]alcoholic[blank_end].
Respuesta
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a Nucleophile
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a Substitution
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an Alcohol
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an Electrophile
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an Elimination
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an Alkene
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warm
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dilute
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aqueous
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hot
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concentrated
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alcoholic
Pregunta 19
Pregunta
Ozone is [blank_start]an allotrope[blank_end] of Oxygen.
Respuesta
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an allotrope
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an isomer
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a variant
Pregunta 20
Pregunta
A Primary Haloalkane is more likely to undergo a Substitution reaction than a Tertiary Haloalkane.
Pregunta 21
Pregunta
A Primary Haloalkane is more likely to undergo an Elimination reaction than a Tertiary Haloalkane.
Pregunta 22
Pregunta
Which of these contribute to the creation of the hole in the Ozone Layer?
Respuesta
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Nitrogen Monoxide
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Aliens
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Carbon Dioxide
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Oxygen
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CFCs
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UV radiation