Organic chemistry Flashcards
what is ethanol
the alcohol in beer, wine and other alcoholic drinks. different drinks contain different amounts of alcohol. e.g. beer is usually 4-6% and vodka 40%
how is ethanol produced. give the word equation
produced from carbohydrates by a process called fermentation. carbon dioxide is also produced in the reaction. carbohydrates can be sugars from fruit, such as grapes. yeast is a fungus. it provides enzymes needed for fermentation to happen.
sugar > ethanol + carbon dioxide
C6H120G(aq) > 2C2H5OH(aq) + 2CO2
explain why fermentation mixture must be kept warm and under anaerobic conditions
reaction is too slow at low temp and yeast enzymes dont work at high temp. fermentation is a type of anaerobic respiration. if oxygen is present, aerobic respiration happens instead, producing carbon dioxide and water
what are the effects of alcohol
increased reaction times, loss of coordination, vomiting. long term = liver cirrhosis and can damage the heart
why is fractional distillation needed
to obtain more concentrated solutions of ethanol
how can you make ethanol from ethene
by reacting ethene with steam in the presence of a catalyst. this is a hydration reaction (water is added). the ethene needed is made by cracking crude oil
how can you make ethene from ethanol
by heating ethanol to high temperatures in the presence of a catalyst. this is a example of dehydration
what are the pros and cons of fermentation
1) fermentation uses a renewable resource
2) quality of ethanol isn’t good, expensive to concentrate and purify ethanol
what is a homologous series
series of compounds that:
> have same general formula
> show a gradual trend in physical properties
> have similar chemical propetrties
how can you tell if a substance is a alkane or alkene or a alcohol
alkenes de-colourise orange-brown bromine water but alkanes and alcohols cannot do this
describe a alkane, structure and features
ends in ane, single bonds, CnH2n+2, saturated, flammable, form carbon dioxide and water when they burn completely
describe a alkene, structure and features
ends in ene, has a double bond, Cn2n, flammable
describe a alcohol, structure and features
ends in ol, has a hydroxol group, CnH2n+1OH, burn with clean blue flame.
how can you form ethanoic acid. how can you use this
by oxidising ethanol. can use this in the manufacture of vinegar
what do you get when you oxidise ethanol
ethanoic acid
what is vinegar, describe its uses
vinegar contains dilute ethanoic acid. used as a flavouring and a preservative because bacteria cannot survive in the acidic environment
describe the structure and features of carboxylic acids
CnH2n+1COOH
how is a ester produced
the reaction between an alcohol and a carboxylic acid produces an ester and water.
give features of a ester
have pleasant, often fruity smells
give 2 uses of esters
used perfumes and as food flavourings because they have pleasant smells
what are polyesters
polymers made from two types of monomer. one type of monomer has a carboxyl group at each end and the other has a hydroxyl group at each end. the two types react together, making polymer molecules containing many ester bonds.
give uses of polyesters
can be made into long thin fibres. these can be woven together to make fabrics. polyesters are also used to make drinks bottles. these can be recycled to make fleece, which is used to make clothing.
how do you make ethyl ethanoate, give the word equation and symbol equation
from ethanoic acid and ethanol:
ethanoic acid + ethanol > ethyl ethanoate + water
CH3COOH + C2H5OH > CH3COOC2H5 + H2O
describe the process of making soaps.
made by boiling oils or fats with a concentrated alkali solution. the esters break down to form:
> an alcohol called glycerol
> sodium salts or potassium salts of carboxylic acids with long carbon chains.
these salts are soaps
