Key Area 2.1 - Homologous Series Flashcards
What is a homologous series
A family of compounds with similar chemical properties that can be represented by the same general formula
Name the alkanes
Methane Ethane Propane Butane Pentane Hexane Heptane Octane
What is the general formula for alkanes
CnH2n+2
What is a fraction
A group of hydrocarbons which have boiling points within a given range
What is fractional distillation
Crude oil is separated into fractions by fractional distillation. This is the separation of crude oil using the varying boiling points of the liquid
Name the fractions
Refinery gas Gasoline Kerosine Diesel fuels Lubricating oils Fuel oil Bitumen
What are the uses for the fraction - Refinery Gas
Heating and cooking
What are the uses for the fraction - Naptha
Petrol
What are the uses for the fraction - Kerosine
Heating and jet fuel
What are the uses for the fraction - diesel
Train car and Lorry fuel
What are the uses for the fraction - lubricating oils
Oils and waxes
What are the uses for the fraction - fuel oil
Central heating and factory fuels
What are the uses for the fraction - bitumen
Roofing and tar for roads
Describe the ease of evaporation
High to low
Describe the size of molecules
Small to large
Describe the boiling point
Low to high
Describe the viscosity
Low to high
Describe the flammability
High to low
What is the general formula for the alkanes
CnH2n
What is the general formula for cycloalkanes
CnH2n
What is the general formula for cycloalkenes
CnH2n-2
What molecules are saturated
Single bonds
Alkanes
What is an addition reaction
Alkenes are more reactive as they contain a double bond. During this reaction the double bond breaks and a molecule such as bromine adds on across the bond
Why is bromine water addition reactions
Naturally brown in colour but when reacted with alkenes it turns colourless immediately
What is a hydrocarbon
Compounds which contain hydrogen and Carbon only
What is catalytic cracking
A chemical reaction which breaks large hydrocarbons into smaller unsaturated and saturated molecules using a catalyst such as aluminium oxide