SC22-24 Organic Chemistry Flashcards
Functional group of alkene
C=C
Functional group of alchohol
O-H
Functional group of carboxylic acid
O=C-O-H
what does unsaturated mean
- contains a double bond
what happens when alcohol is oxidised
forms a carboxylic acid + water
What happens when an alcohol is combusted (completely oxidised)
- forms CO2 + H2O
Test for alkene
bromine water goes colourless
addition reaction takes place
Why are these alkanes neighbouring members of the same homologous series
same general formula
differ by CH2
products of cracking
converts long alkanes and alkenes into smaller chain molecules of:
small alkenes
hydrogen
cracking reaction is
endothermic
why is cracking necessary
supply and demand, lighter fractions are more useful and outweigh the supply so larger, heavier fractions are cracked
catalytic cracking
heating hydrocarbons to around 500 degrees
vaporise them
pass over hot aluminium oxide catalyst
thermal decomposition
broken up in a random way
produces a mix of smaller alkanes and alkenes
steam cracking
higher temperature
produces more ring structes and unsaturated compounds
how are condensation monomers formed
two different monomers are linked together and a small molecule (water usually) is removed
what happens when an ester link is formed
one molecule loses OH on both ends
other loses H on both ends
dicarboxylic acid
carboxylic with a functional group at each end
disposal methods of polymers
- landfill - non-biodegradeable
- incineration - release toxic gases and carbon dioxide
- recycling - difficult and expensive
advantages of recycling polymers
- more economically viable than from scratch
- decreases use of crude oil
- better for environment
- reduces landfill
- creates jobs and economic growth
disadvantages of recycling polymers
- sorting plastics is labour intesive + tedious
- recycling can only use what has been collected as raw materials
- produces toxic gases to melt
- can only be recycled so many times
- risk of mixing polymers, effecting their properties, dangerous in aircraft, cars etc.
simple carbohydrates
monosaccharides like sugars
complex carbohydrates
polysaccharides like starch
condensation polymers made from sugar monomers
proteins
condensation polymers formed from
amino acid monomers
peptide bonds
amino acids
small molecules containing
carboxylic functional group
amine (-NH2)
what forms a peptide link
when a carboxylic acid and amine react
fermentation conditions
suagr or starch is dissolved
yeast is added
between 15 to 35 degrees
no oxygen
why add yeast to fermentation
yeast contains enzymes that break down sugar into alcohol
point of fermentation
turns sugars into alcohol
how is ethanol purified
fractional distillation
78 degrees
condenser
