alcohols Flashcards
what does a primary alcohol oxidise into
aldehyde
what does a secondary alcohol oxidise into
ketone
what does a tertiary alcohol oxidise into
does not oxidise because there is no hydrogen for it to oxidise with
what are the three definition of oxidation
loss of electrons
loss of hydrogen
gain of o2
what are the three definitions of reduction
gain of electrons
gain of hydrogen
loss of o2
what happens when you dont immediately distil off a primary alcohol
it will turn straight into a carboxylic acid and miss out the aldehyde step
define a base
proton acceptor
what does acid + alkali =
salt and water
why should dichromate handled with care
dichromate is a carcinogen = toxic
how can aldehydes and ketones be turned back into alcohols
a strong reducing agent
how to turn a alcohol to an alkene
conc h2so4 or h3po4 (dehydrating agent)
under warm reflux
how can an acid catalyse a reaction
by protonating a carbonyl group
how can an alkali catalyse a reaction
by deprotonating an alcohol
how can glucose be turned into ethanol
in the absence of air yeast will catalyse the production of ethanol and carbon dioxide from glucose.
conditions - at 35-55 degrees
what are some advs to fermentation reactipn
cheap
renewable becausr the glucose comes from sugar cane (plant)
low tech
can be done pretty much anywhere
low energy
what are some dadv to fermentation
slow process
what does a metal and a carbonate make
h2o +co2 +salt
describe the process of fermentation
an exothermic reaction
carried out by yeast in anaerobic conditions
C6H12O6 (aq)———-> 2C2H5OH(aq) +2CO2(g)
yeast is the catalyst at 30-40 degrees
define carbon neutral
no net release of carbon
what is an advantage of biofuel
renewable energy source
most biofuels are considered carbon neutral
what are some dadvs or biofuel
using land to grow the crops that will just be burned and not using the space for growing food
- deforestation
- destruction of habitats to grow plants = decrease in biodiversity
give the equations to show that ethanol is a carbon neutral fuel source
6CO2 +6H2O—–> C6H12O6 + 6O2
C6H12O6 —–>2C2H5OH +2CO2
2C2H5OH +6O2 —–> 4CO2 +6H2O
across these three equations six molecules of carbon dioxide went in and 2+4 came out
why might some people not think ethanol is carbon neutral
to power the machinery to farm the crops. refining and transporting the bioethanol also uses energy.
