organic chemistry 2 Flashcards
homologous series
family of compounds, same functional group, similiar chemical properties and physical properties
functional group
part of molecule that largely dictates how molecule will behave
what are alchols functional group
OH- hydroxide
what is alchols general formula
Cn H2n+2 O
isomers
molecules with same molecular formula but different structures
what are some uses for alchols
fuels, drink, clean, sterilize
what alchols are normally used as fuels
methanol and ethanol
what type of fuel is ethanl
ethanol is a biofuel in cars, burns with clean blue flame
combustion of ethanol word equation
ethanol + oxygen -> carbon dioxide + water
biofuel
fuel made from biological sources
fuel
substance that releases energy when burned with oxygen
what are two ways to produce ethanol
hydration of ethene
fermentation
symbol and word equation for fermentation
C6H12O6 -> C2H5OH + CO2
glucose -> ethanol + carbon dioxide
(exothermic process)
what is needed for fermentation to happen
enzyme- yeast (catalyst)
temperature- 30 degrees
anaerobic (absence of oxygen)
advantages of using fermentation
low energy needed (to not denature enzyme), renewable resource, cheaper,
disadvantages of using fermentation
The use of crops for fermentation could impact on food supply, not continuos process, requires impure product to be refined by fractional distillation as carbon dioxide also produced, slower
word and symbol eqaution for hydration of ethene
C2H4 + H2O -> C2H5OH
ethene + water -> ethanol
what is needed for hydration of ethene to take place
temp- 300 degrees
pressure- 60-70atm
catalyst- phosphoric cid
advantages of hydration of ethene compared to fermentation
continuos process, little input for human workers, yields pure ethanol, fast process
disadvantages of hydration of ethene compared to fermentation
uses high temp thus expensive, non renewable resource use fossil fuels
properties of ethanol
liquid at room temp, volatile, boiling point of 78 degrees, highly flammable, burns readily with oxygen with clean blue flame, releases a lot of heat energy when burned does not release soot, can be used as a solvent
uses for ethanol
used as a solvent, eg cosmetics (safe for human contact) or perfumes (diffuses quickly), fuel as combustion highly exothermic
why is ethanol used as a biofuel in brazil, what is a disadvantage
cheaper than gasoline, lots of land for agriculture such as sugar can, used to produce ethanol, low labor cost however because of land needed for agriculture, defloristtion takes place, realses co2, monoculture, not food for population consuming
what is a carboxylic acid
an organic compound containing a –COOH functional group
strong acid vs weak acids
strong-fully dissociates in aqueos solutions, weak partially
properties of carboxylic acids
very soluble in water, weak acid, characteristic smell
name first 5 carboxylic acid
methanoic, ethanoic, propanoic, butanoic, pentanoic
two ways in which ethanoic acid can be made
both are via oxidation of ethanol
1. reacting ethanol with acidified aqueos potassium mangante
2. by bacterial oxidation during vinegar production
word equation and symbol for reacting ethanol with acidified aqueos potassium mangante
ethanol-> ethanoic acid
C2H6O -> CH3COOH
whats necessary for reaction of ethanol to becoem ethanoic acid,when using potassium mangante
100 degrees, KMnO4, H2SO4
word and symbol equation for bacterial oxidation during vinegar production
ethanol + oxygen -> ethanoic acid + water
C2H6O + O2 -> CH3COOH +H2O
what happens when metals react with acid
salt and hydrogen produced
what happens when acid react with base
salt and water produced
what happens when acid react with carbonate
salt, water, carbon dioxide produced
ending of salts from carboxylic acids
…. methanoate
…. ethanoate
…..propanoate
…..butanoate
…..pentanoate
symbol for ethnoic acid
CH3COOH
explain a bit of process of making ethanoic acid from potassium mangante
Potassium manganate(VII), KMnO4 is a strong oxidising agent and is used in the presence of sulfuric acid and heat to produce ethanoic acid
ester
An organic compound, containing a –COO– group, that is produced when an alcohol reacts with a carboxylic acid.
example of ester use
esters are fragrant so they are used as flavouring in food and in cosmetic products
how are esters produced
reaction between carboxylic acids and alchols in presence of acid catalyst
what is esterification
producing an ester
what does the reaction between ethanol and ethanoic acid produce
ethyl ethanoate and water
process of creating an ester (bond breaking and making)
the C–O bond of the OH hydroxyl group in ethanoic acid breaks
the O–H bond in ethanol breaks
the two remaining parts from each molecule join together forming a C–O bond for the ester
OH and H combine to form water (a condensation reaction).
symbol equation of production of ethyl ethanoate
CH3COOH + C2H6O -> H2O + C4H8O2
how do you name esters?
you take the carboxylic acid name eg methanoic acid, and the alcohol name eg. propanol and use the start of the alcohol and the ending of the acid eg. propyl methanoate
to form an ester what happens with the bonds in the carboxylic acid and the ones in the alcohol
in the alcohol, the hydrogen bond with oxygen from the OH, is removed
in the acid, the entirety of the OH bond from the C is removed
these are used to form H2O
what are polymers
large molecules built up from many smaller molecules called monomers
what is polymerisation
the process in which small molecules called monomers become a polymer
structure of polyamides
made from a diamine and a dicarboxylic acid
structure of polyester
made from a diol and a dicarboxylic acid
name of polymer made from ethene monomers
poly(ethene)
what is addition polymerisation
When single units of an alkene (monomer) join together to form a very long chain (polymer). only forms one product
what is an advantage of using PET?
it can be converted back into monomers and re-polymerised
what is a repeat unit
The smallest section of a polymers structure that can accurately represent the whole molecule.
describe proteins
natural polyamides, formed from amino acid monomers
what are plastics made from
polymers
how do you draw a repeat unit
you put brackets and a “n” outside the bracket, and break the double bond present in the alkene
what happens in a condensation reaction?
two smaller molecules join to produce a larger molecule and a smaller molecule, usually water
what is meant be biodigradble
The ability of materials to decompose by the action of microorganisms.
two examples of condensation polymers
polyamides and polyesters
what is a dicarboxylic acid
molecule containing two COOH groups
what is a diamine
molecule containing two NH2 groups
what is an amide link
chemical bond in polyamides
-CONH-
what is a common polyester?
PET
what is a diol
molecule containing two OH groups
what is an ester link?
chemical bond in polyester
-COO-
what is PET used for?
making drink bottles
making insulating fibres for clothing
what can you do to waste PET?
convert it back to its monomers so it could be repolymerised (in order to make new PET products)
land fill problem with plastic
waste materials buried in land fill, then covered with soil, however suitable land for this is becomign difficult to find, or fill up fast. as plastics break downsome particles can be washed out with ground water, this “leachate” contaminate near by rivers and lakes.
general structure of amino acids
NH2 group and COOH group
general structure of an amino acid (diagram)
the R stands for a side group
what can R be in an amino acid, and what does it mean
R - side group
different amino acids have different side groups
how is an amide link formed (amino acids)? what happens in this reaction?
COOH group on one monomer reacts with NH2 group on another monomer
molecule of water also eliminated
