UNIT 3 - Year 1 Organic Chem Flashcards
(48 cards)
what are the 5 features of a homologous series
- same functional groups
- same general formula
- similar chemical properties
- each successive member differs by CH2
- gradually changing physical properties
what is a hydrocarbon
a hydrocarbon is a compound made up of only carbon and hydrogen
what is a general formula
represents the homologous series of compounds using letters and numbers
what is a structural formula
shows how atoms are bonded to each carbon atom in a molecule
what is a displayed formula
representation of an organic comound and all its atoms and their bonds
what is a skeletal formula
formula with all the carbon adn hydrogen bonds assumed
what is a molecular formula
shows the number and type of each atom in a molecule
what is an empirical formula
the simplest whole number ratio of the elements present in a molecule
what is structual isomerism
the same molecular formula but a different structural formula
what are the 3 different types of structural isomerism and explain them
functional group- different functional groups
chain- different longest carbon chain length
position- functional/ alkyl group is on a different carbon
what is stereoisomerism
compounds with the same molecular and structural formula but atoms are arranged differently in space
what is geometric isomerism
have the same molecular and structural formula but the groups on the double bond can be switched above or below
what is an E isomer and what is a Z isomer
what does the difference between them cause in properties
an E isomer have functional groups on opposite sides of the double bond
a Z isomer have functional groups on the same side of the double bond
they hve very different chemical and physical properties
explain the process of fractional distillation
- it is carried out in a fractioning column which has a heat gradient at the top it is cool and at the bottom it is very hot
- crude oil enters the fractioning column and is heated so vapour rises
- vapours of hydrocarbons with low B.Ps will rise up the column and condense at the top to be tapped off and the fractions will high B.Ps will be at the bottom
what is the problem with fractional distillation (what does it miss)
crude oil contains small amounts of compounds containing sulphur and when burned it can form sulfur dioxide
what is the order of fractions in fractional distillation
- refinary gases
- petrol
- naptha
- kerosene
- gas oils
- mineral oils
- residue: wax, grease, bitumen
what is cracking and why do we use it
cracking is the breaking of long chain hydrocarbons into smaller ones as the smaller ones are more useful
what are the two types of cracking
what are the conditions
what are the products
thermal and catalytic
thermal- high temperatures and high pressure to produce alkanes and mainly alkenes
catalytic- lower temp and slight pressure in the presence of a zeolite catalyst to produce alkanes and aromatic hydrocarbons
what are the two types of combustion and what are the conditions and products of them
complete- in excess oxygen to produce CO2 and H20
incomplete- limted supply of oxygen to form CO,CO2,soot and H2O
what can car exhaust fumes contain?
carbon monoxide
nitrogen oxide
volatile organic compounds
how is nitrogen oxide produces in cars and what are the dangers of it?
high temperatures in the engine cause nitrogen to react with oxygen and nitrous oxides are released into the air
-they can dissolve and react with water to from nitric acid which causes acid rain
-they can also react with unburnt hydrocarbons to create VOCs which form smog
what is the role of catalytic converters and what is their structure
reduce the amount of pollutants released in car exhaust fumes
coated in a honeycomb structure of precious metals like: platinum,palladium and rhodium to increase the surface area
what is the equation/s for catalytic converters removing CO from the air
2CO + O2 –> 2CO2
or
2CO + 2NO –> 2CO2 + N2
what is teh equation for removiing nitrous oxides from the air in catalytic converters
2CO + 2NO –> 2CO2 + N2
