C9 Crude Oil And Fuels Flashcards
What is the definition of a hydrocarbon?
A molecule comprised of only hydrogen and carbon atoms
What is the general formula of an alkane?
C(n) H(2n+2)
What type of molecules are alkanes?
Saturated
What makes alkanes saturated?
They contain only C-C single bonds
State the first four alkanes and their structures
Methane (CH4)
Ethane (C2H6)
Propane (C3H8)
Butane (C4H10)
What is the viscosity of a liquid?
The “thickness of a liquid”
High viscosity liquids flow slower
Describe how the size of a hydrocarbon affects its viscosity
As the size of the hydrocarbon chain increases, so does the viscosity
Describe how the length of a hydrocarbon chain affects its flammability
The shorter the hydrocarbon chain, the greater its flammability
Describe how the length of a hydrocarbon chain affects its boiling point
The shorter the hydrocarbon chain, the lower its boiling point
What are the products of complete combustion?
Carbon dioxide and water
What are the products of incomplete combustion?
Carbon monoxide and water
Why does incomplete combustion occur?
Due to a limited oxygen supply
What is combustion?
Burning in oxygen (to release energy)
Describe the process of fractional distillation of crude oil
Firstly the crude oil is heated to a high temperature to boil it. The crude oil vapour is fed into the fractional distillation column, which is hotter at the bottom, and cooler at the top. The vapour rises up the column, and hydrocarbons condense when they reach their boiling point, and the liquid fractions are then removed. The remaining hydrocarbons continue moving up the column and condense when they reach their boiling points. Very short chain hydrocarbons have low boiling points and don’t condense, and are removed from the top of the column as gases
What are Fractions?
Hydrocarbon chains with a similar number of carbon atoms
What Hydrocarbons fractions are used to fuel cars?
Petrol and Diesel