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sn1 and sn2 practice

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Nucleophilic Substitution 5N1 and 5N2 Summary Questions
t Isa nucleophile? Give some examples of nucleophiles‘.
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Why
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do nucleophiles attack the carbonhalogen bond of a halogenoadane?
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What is the genera! equation for the reaction of a halogenoalkane and a strong ba
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Write the general equation for Nucleophilic Substitution (showing the nucleophile and Halogen (X))
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What'Is heterolytic fission?
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tep, 1 (prImary)... In the dIagrams below, show the m o v e m e n t of the electron pairs with the curly arrow...
Nucleophile attacking
Unstable transition state (with
Formation of alcohol and the release of
halogenoalkane from the back
nucleophile and halogen both
the leaving group (halide)
attached by weak bonds)... Show the
charge on the molecule".
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Why (tees the 5N2 mechanism favour primary halogenoalkanes and n o t tertiary? (Think
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Explain why the SN2 mechanism is bimoiecuiar Write the rate equation for this mechanism
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What happens to the arrangement of the a t o m s around the carbon a t o m after 5N2?
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5N1, 2 Step, 3° (tertiary)... in the diagrams below, show the m o v e m e n t of the electron pairs with the curly arrow...
Step 1: Heterolytic fission of the carbon‐haiogen bond
Step 2: Carbocation intermediate attacked by nucleophiie
(ionizes the halogenoaikane).
leading to n e w bond...
Halide ion will leave, producing a carbocation
intermediate.
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The presence of 3 alkyi groups on the tertiary haiogenoalkane has what effect on the carbocation?
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Explain why the 5N1 mechanism is unimoiecuiarI Wr i t e the r a t e equation for this mechanism.
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Which nucleophilic substitution mechanism do 2° (secohdary) haldgenoalkanes undergo?
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Factors t h a t affeCt the rate of nuci’eOphii
What are the three factors that affect the r a t e
of nucleophiiic substitution?
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Give the order
of rates according to the type of halogenoalkanei Start with the fastesthalogenoatkane and annotate
which SNmechanism is applicable under each halogenoalkanei
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Explain how the influence of the leaving group involves:
(a) polarity of the carbon‐halogen bond
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(b) strength of the carbon-halogen bond
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Describe which (polarity or strength) of the carbon-haiogen bond is the dominant factor for determining rate.
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Explain which solvents (polar & protic/polar & aprotic) are favoured by:
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Explain the statement above using understanding about:
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10, 20 and 30halogenoalkanes
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the mechanisms they favour
which is the best carbon~halogen bond (in t e r m s of rate)
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the Choice of solvent that each mechanism favours
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