organic chemistry 1 Flashcards
what are the fossil fuels
coal, natural gas and petroleum
what is the main constituent of natural gas
methane
what are hydrocarbons
compounds only containg hydrogen and carbon
what is petroleum
a mixture of hydrocarbons
how is petroleum seperated into useful fractions
through fractional distillation
what are the changing characteristics from the bottom to the top of the fractionating column
decreasing chain length, higher volatility, lower boiling points, lower viscosity
what is refinery gas used for
gas used in heating and cooking
what is gasoline/petrol used for
fuel used in cars
what is naptha used for
chemical feedstock
what is kerosene/paraffin used for
jet fuel
what is diesel oil/gas oil used for
fuel in diesel engines
what is fuel oil used for
ships and home heating systems
what is lubricating oil used for
lubricants, waxes and polishes
what is bitumen used for
for making roads
what is the order of products in the fractional distillation column bottom to top
bitumen, fuel oil, lubricating oil, diesel, kerosene, naphtha, petrol, refinery gas
what is a homolegues series
family of similiar compounds which have similiar chemical properties and have the same functional group, same general formula, trend in physical properties, differ from one member to teh next by a CH2 unit
what is the general formula of alkanes
Cn H2n+2
what is the general formula of alkenes
Cn H2n
what is a functional group
an atom or group of atoms that determine the chemical properties of a homologous series
structural formula
an ambiguous description of the way the atoms in a molecule are arranged
what is a saturated compound
has molecules in which all carbon carbon bonds are single bonds (alkanes)
what is an unsaturated compound
has molecules which have at least one carbon carbon double bond (alkenesO
what are fossil fuels
non renewable resources that when burned produce energy
name the first 5 beginings of hydrocarbons
meth
eth
prop
but
pent
what is isomerism
whem molecules have the same molecular formula but different displayed formula
how can you distinguish between alkenes and alkanes
add browmine water, if it is an alkene goes from orange to colourless, else remains orange
what happens when an alkane react with halogen
- only reacts with presence of UV light, (photochemical reaction) because it provides activation energy needed
-one of the hydrogens of the alkane is substituted by the halogen, and in addition produces another product of only a hydrogen and the halogen used
eg:
H-Br
-called substituion
what happens when an alkene react with halogen
-no UV light needed
-only has one product, both halogen atoms join onto hydrocarbon
-called adition
what is the bonding in alkanes + properties
single covalent and are saturated hydrocarbons
generally unreactive except on terms of combustion and substiution with chlorine
what is the bonding in alkenes
include a double carbon-carbon covalent bond and are unstaturated hydrocarbons
describe properties of alkenes
react with bromineor aqueos bromine
react with hydrogen in presence of nickel catalyst
react with steam in presence of an acid catalyst
in general more reactive than alkanes
how are alkenes and hydrogen manufactured
by the cracking of larger alkane molecules using high temp and a catalyst
what is combustion
scientific word for burning in presence of oxygen and light energy is released during it
give the formula for complete combustion
hydrocarbon + oxygen -> carbon dioxide + water
(both carbon and hydrogen are oxidised)
what is incomplete combustion
combustion in the shortage of oxygen, instead of producing just carbon dioxide and water it produces carbon monoxide and/ or carbon (soot)
also releases less energy
what is carbon monoxide
a colourless and odourless gas, it is poisonous and binds irreversibly with haemoglobin in your blood reducing ability of it to carry oxygen.
what is cracking
the process that splits long chain alkanes into shorter chain alkanes and lakenes
useful becaus elong chain alkanes can be turned into short chain alkanes/alkenes that can be used for fuels or plastics
what are the conditions for cracking to happen
very high temperature and aluminium oxide or ceramic catalyst
