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What is the functional group of an alcohol?
-OH
What is the general formula for alcohols?
CₙH₂ₙ₋₁OH
How do you name alcohols?
hydroxy-, -ol
What kind of intermolecular forces do alcohols have?
hydrogen bonding
Why do alcohols have hydrogen bonding?
the OH bond is highly electronegative
How do alcohols’ melting and boiling point compare to hydrocarbons of similar carbon chain lengths?
higher melting/boiling points
Why do alcohols have higher melting and boiling points as hydrocarbons of similar chain length?
hydrogen bonding is stronger than London forces
Are alcohols soluble in water?
soluble in short chains - hydrogen bonding with water
insoluble in long chain - non-polarity of CH bond takes precedence
What is a primary alcohol?
the C with the -OH group is bonded to one other Carbon atom
What is a secondary alcohol?
the C with the -OH group is bonded to 2 other carbon atoms
What is a tertiary alcohol?
the C with the -OH group is bonded to 3 other carbons
What forms when you partially oxidise a primary alcohol?
aldehyde -CHO
What conditions are needed to partially oxidise a primary alcohol?
dilute H₂SO₄
potassium dichromate(VI) / Cr₂Kr₂O₇
distill product as it’s produced
gentle heating
What is the equation for the partial oxidation of ethanol?
CH₃CH₂OH + [O] → CH₃CHO + H₂O
What forms when you fully oxidise a primary alcohol?
carboxylic acid, -COOH
What conditions are needed to fully oxidise a primary alcohol?
conc. H₂SO₄
K₂Cr₂O₇
reflux
strong heat
What is the equation for the full oxidation for ethanol?
CH₃CH₂OH + 2[O] → CH₃COOH + H₂O
What forms when you oxidise a secondary alcohol?
ketone
What conditions are needed to fully oxidise a secondary alcohol?
conc. H₂SO₄
potassium dichromate (VI)
strong heating
What is the equation for the oxidation of propan-2-ol?
CH₃CH(OH)CH₃ + [O] → CH₃COCH₃ + H₂O
Is it possible to oxidise a tertiary alcohol?
no
What is a dehydration reaction?
a reaction in which water is lost to form an organic compound
What are the products of a dehydration reaction with alcohol?
alkene and water
What conditions are required for the dehydration of alcohols?
conc. H₂SO₄
conc. H₃PO₄
170°C
What products are formed in halide substituition with alcohol?
haloalkane and water
What conditions are needed for an alcohol to form a halogenoalkane?
NaX
H₂SO₄
heated under reflux
What are haloalkanes?
saturated organic compunds that contain carbon atoms and at least one halogen atom
Are haloalkanes soluble in water?
no
Why aren’t haloalkanes soluble in water?
C-H bonds are non-polar, not compensated for enough by C-X bond polarity
Do haloalkanes have a polar bond?
Yes, halogen has a higher electronegativity than C
Which intermolecular forces do haloalkanes have?
permanent dipole-dipole, London forces
What causes an increase in the boiling point of a haloalkane?
increased 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 (halogen mass > carbon mass)
What is the most important factor in determining halogen reactivity?
strength of the carbon-halogen bond
What would bond polarity suggest the order of reactivity of haloalkanes would be?
C-F would be the most reactive (most polar)
What does bond enthalpy suggest the order of reactivity of haloalkanes would be?
C-I would be the most reactive (lowest bond enthalpy)
What is a nucleophile?
electron pair donor
What are some examples of nucleophiles?
:OH⁻, :CN⁻, :NH₃⁻, :Cl⁻
What is nucleophilic substituition?
a nucleophile donates a lone pair of electrons to a C⁶⁺ atom and the ⁶⁻ atom is replaced by the nucleophile
What is hydrolysis?
reaction in which water is a reactant
Which reactant often produces hydroxide ions for hydrolysis?
water/H₂O
What fission does water undergo to produce OH⁻?
heterolytic
What are CFCs?
chlorofluorocarbons (haloalkanes containing only C, Cl, F)
What is the problem with CFCs?
catalyse the breakdown of ozone in the atmosphere (via free radical substituition)
What is the main function of the ozone layer?
provides protection from harmful UV rays
Does ozone protect in all layers of the atmosphere?
no, in the troposphere it contributes toward photochemical smog
How do CFCs break down the ozone layer?
free radical substituition
What is the overall equation for the decomposition of ozone?
2O₃ → 3O₂
What is the initiation step for the breakdown of ozone?
Cl₂ → 2Cl∙
What are the propagation steps for the breakdown of ozone?
Cl∙ + O₃ → ClO∙ + O₂
ClO∙ + O₃ → 2O₂ + Cl∙
Note 
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