Reaction of Alcohols Flashcards
what is the oxidising agent needed for alcohols?
acidified potassium dichromate (VI) (H2SO4/K2Cr2O7)
what happens during oxidisation?
colour change will take place due to changing chemical state of acidified potassium dichromate
starts of orange to green to a blue solution
what does acidified potassium dichromate supply?
oxygen [O]
what does oxidation with a primary (1°) alcohol produce?
with stoichiometric [O] (1:1 ratios of alcohol and oxidising agent)
an aldehyde
what does oxidation with a primary (1°) alcohol produce?
with 2 equivalents of oxidising agent for one part of alcohol)
carboxylic acid with excess [O]
what does oxidation with a secondary (2°) alcohol produce?
ketone
what does oxidation with a tertiary (3°) alcohol produce?
it resists oxidation (under certain conditions)
only resists with acidified potassium dichromate
how to name aldehyde
name corresponding alkane
drop ‘e’
add suffix ‘al’
how to name carboxylic acid
name corresponding alkane
drop ‘e’
ass suffix ‘oic acid’
how to name ketones
name corresponding alkane
drop ‘e’
add suffix ‘one’
(if chain has 5 carbons or more need to number position of double bond)
how to name chloroalkane
name corresponding alkane
add prefix ‘chloro’
number position of -cl (if chain has more than three carbons)
under what condition does chlorination with thionyl chloride (SOCl2) need to take place?
under dry conditions (no water) as SOCl2 reacts very quickly with water.
what does dehydration (elimination) do?
removes or eliminates water from the molecule
what is C.H2SO4 used as during dehydration?
as a catalyst and dehydrating agent
what does dehydration require to be carried out ?
heat
def of elimination
loss of small molecule
def of dehydration
loss of water
example of esterification
condensation reaction
where two molecules join together with a loss of a small molecule (often H2O but not always)
what else is condensation reaction known as?
addition-elimination
what needs to happen during the process of esterification with carboxylic acid? ( reacting an alcohol with carboxylic acid)
these reactions need to be heated up with H2S04 (acts as a dehydration agent). so it will chemically absorb the water on the right-hand side (refer to the equation)
how to name ester
name alkyl with no oxygen
name part with two oxygens using suffix ‘oate’
esterification example
reacting alcohol wit carboxylic acid
how to make an ester
carboxylic acid + alcohol
how do esters form?
alcohols + carboxylic acid
carboxylic acid loses OH group
alcohol loses H from its OH group
these two groups then bond together and the other part of the equation is the lost OH and H to form a water molecule (H20) is a byproduct
where is a C double bond in a ketone?
middle
during chlorination what does the OH replace in the equation?
(alcohol + thionyl chloride)
Cl (CHLORINE)
what are the by-products during chlorination?
alcohol + thionyl chloride
SO2
HCl
under what conditions does chlorination take place?
alcohol + thionyl chloride
dry conditions
what product is made during chlorination?
alcohol + thionyl chloride
halogenoalkane or chloroalkane
during dehydration (elimination) what is taken away from the beginning of the equation?
OH and its adjacent H
in what state does dehydration (elimination) take place?
heat
what is the best way to write the equation for esterification?
best to start equation with alcohol
best to write full structural formula
best to point fictional groups towards each other (in first part of the equation).
what condition does esterification take place?
heat with conc sulfuric acid. (H2S04)
what reagent does chlorination need in order to take place?
thionyl chloride (SOCl2)
what sort of reaction occurs when alcohols react with carboxylic acid?
condensation/elimination
