T7 organic chemistry

mixture of compounds; a fossil fuel consisting of the remains of ancient biomass finite resource - can’t be replaced as it is used up

compound made up exclusively of hydrogen and carbon atoms

saturated hydrocarbons of a general formula CnH2n+2 (where n is the number of carbon atoms in the molecule).

series of compounds with same general formula, same functional groups and similar chemical properties

• exothermic reaction occurring when hydrocarbons are reacted with oxygen • complete combustion produces carbon dioxide and water (carbon and hydrogen atoms are completely oxidised) • incomplete combustion produces carbon or carbon monoxide and water

• first few in series are gases, then change to liquids, then to solids • in general, boiling points and viscosity increase as molecules get bigger • volatility and flammability decrease as molecules get bigger • poor reactivity

• crude oil is heated and vaporised • vapor rises up the fractionating column • column is hotter at bottom • hydrocarbons cool as they go up the column and condense at different heights as they have different boiling points • large molecules, high boiling points, collected at bottom • this gives fractions which can be used in various ways

when large hydrocarbons are thermally broken down into smaller and useful molecules

thermal decomposition

reactant heated to vapor, passed over a hot catalyst (catalytic cracking) or heated to vapor, mixed with steam and heated to high temperatures (steam cracking)

products are alkanes and alkenes - used as polymers and starting materials for synthesis

unsaturated hydrocarbon, contain C=C bond general formula CnH2n

add bromine water colour change occurs from orange to colourless

burn with smoky flames due to incomplete combustion

additions atoms across the carbon-carbon double bond so that the double bond becomes a single carbon-carbon bond a. with hydrogen - hydrogenation; requires a higher temperature and a nickel catalyst b. with steam - hydration; requires high temperature, pressure and concentrated phosphoric acid (H3PO4) as a catalyst c. with Br2/Cl2/I2 - addition of halogens

organic compound that contains and -OH functional group

• dissolve in water to form a neutral solution • react with sodium to form hydrogen • burn in oxygen • react with carboxylic acids in presence of acid catalyst to form esters

carboxylic acids

fuels solvents drinks

30C, aqueous solution of the glucose, absence of air, yeast added C6H12O6 > 2CH3CH2OH + 2CO2

organic compounds that contain a COOH functional group

• dissolve in water to form an acidic solution (contains H+ ions) • react with metal carbonates to form carbon dioxide • react with alcohols with an acid catalyst to produce esters • react with metals to give off hydrogen gas

weak aid

partially dissociated in water, thus the pH of a carboxylic acid in solution is not as low as a solution of a strong acid of the same concentration