module seven - revision deck Flashcards
alkane general formula
CnH2n+2
characteristics of alkanes, alkenes and alkynes
saturated hydrocarbons
non-polar
dispersion forces
generally low boiling points, increase as carbon chain increases
alkene general formula
CnH2n
Alkyne general formula
CnH2n-2
alcohol general formula
CnH2n+1OH
primary alcohol
one in which only one carbon atom is bonded to the carbon atom attached to the OH group
carbonyl function group
oxygen double bonded to a carbon
aldehyde
carbonyl group attached to a terminal carbon atom of the chain
suffix -anal
ketone
carbonyl group attached to a middle carbon
suffix - anone
carboxyl group
carbon double bonded to an oxygen and a hydroxyl group
amine general formula
R-NH2
amines
contained NH2 attached to a hydrocarbon chain
can be classified as either primary, secondary or tertiary depending on how many hydrocarbon groups are attached to the nitrogen
amide
contains a carbon double bonded to an oxygen as well as an NH2 group
formed from carboxylic acids when the hydroxyl group is replaced by an amine group
amide general formula
RCONH2
isomer
molecules that have the same molecular formula but their atoms are arranged differently
chain isomers
involve rearrangement of the carbon skeleton
position isomers
made by moving the position of the functional group
functional group isomers
compounds with the same molecular formula but a different functional group
intramolecular bonds in alkanes, alkenes, alkynes
strong covalent bonds
shape of single bonded carbon molecules
tetrahedral with a bond angle of 109.5 degrees
shape of carbon carbon double bond
trigonal planar with bond angle of 120 degrees
shape of carbon carbon triple bond
linear with a bond angle of 180 degrees
environmental impact of hydrogens
mining for crude oil and natural gas is often ocean-based
oil spills can cause severe environmental damage
burning fossil fuels releases carbon dioxide, a greenhouse gas
production and transport of fossil fuels causes methane emissions
Exxon Valdez Oil Spill
1989 Exxon Valdez oil spill in alaska saw 41 million litres of oil spilled, contaminating > 1800km of coast lines, causing four human deaths and hundreds of thousands of animal deaths
greenhouse gas definition
cause heat to be trapped in the earth’s atmosphere causing global warming
economic impact of hydrocarbons
reliable energy source for industries
global economy is reliant on effective and reliable transportation which is primarily fuelled by hydrocarbons
leads to job creation
sociocultural impacts of using hydrocarbons
polymers are used in packaging, clothing, homewares, varnishes and adhesives
can be used to create medicines and pharmaceutical drugs
reliable and quick source of energy to power our lives
relatively inexpensive and accessible source of energy
addition reactions
unsaturated molecules undergo addition reactions where two or more molecules are joined to form a larger molecule
halogenation
alkene + halogen –> dihaloalkane
hydrogenation
alkene + hydrogen –> alkane
usually occurs in the presence of a metal catalyst such as nickel, platinum, palladium or rhodium
hydration
alkene + water –> alcohol
requires a dilute sulfuric acid catalyst
hydrogen halide addition
alkene + hydrogen halide –> haloalkane
Markovnikov’s rule
when a compound of the form HX is added to an asymmetrical alkene, the hydrogen becomes attached to the carbon with more hydrogens already attached to it
substitution reactions
occur in saturated molecules where one species on a molecule is replaced by another
alkane substitution with halogens
alkane + halogen –> haloalkane + hydrogen halide
the halogen molecule is broken up in the presence of UV light, creating a free radical
the free radical replaces one of the hydrogens on the alkane creating a haloalkane and a hydrogen halide