4.5 ORGANICS I Flashcards
Crude oil is a mix of what
Hydrocarbons
Define a hydrocarbon
A compound of hydrogen and carbon atoms only
What do each fraction of crude oil have in common
They are similar size hydrocarbons with similar boiling points
As the boiling points of fractions of crude oil increase, what trends occur
- The fractions get darker in colour
- The fractions get more viscous
What is the fraction with the lowest boiling point
Refinery gases
What is the fraction with the 2nd lowest boiling point
Gasoline
What is the fraction with the 3rd lowest boiling point
Kerosene
How many fractions of crude oil are there
6
What is the fraction with the 3rd highest boiling point
Diesel
What is the fraction with the 2nd highest boiling point
Fuel oil
What is the fraction with the highest boiling point
Bitumen
Why does the molecular mass increase, as the fractions boiling points increase?
They have more carbon and hydrogen atoms as the fractions go down the fractionating column
Use of refinery gases
Fuel for home cooking
Use of gasoline
Fuel for cars
Use of kerosene
Fuel for aircraft
Use of diesel
Fuel for trains
Use of fuel oil
Fuel for ships
Use of bitumen
Making roads
Describe the process of fractional distillation
- Heated crude oil vapours enter the column
- Vapours rise until they reach their boiling point, where they condense
- Different vapours condense at different heights due to their different boiling points
- Similar vapours condense together as a fraction
Define a fraction
Mixtures containing hydrocarbons that boil in a particular temperature range
What temperatures does kerosene boil at
250-350c
Alkane general formula
CnH2n+2
Name the alkanes according to the number of carbon atoms they have
- Methane
- Ethane
- Propane
- Butane
- Pentane
How is a displayed formula shows
Shows the position of every atom and bond
How is structural formula shown
The structure of molecules in one line
CH3 CH2CH2CH3
What are the functions of a homologous series
- Similar chemical reactions
- Trends in physical properties - (Boiling point)
- Same general formula - (Alkenes are CnH2n)
- Same functional group - (alkanes are all C-C)
Define an isomer
Molecules with the same molecular formula but different structural formulae
What are butanes 2 isomers
- Standard chain of carbon atoms with hydrogen off each one
- 3 carbon atoms in a chain with an extra off the middle carbon atom and 3 hydrogen atoms off that
What are pentanes 3 isomers
- Standard chain of carbon atoms with hydrogens off each one
- Chain of 4 carbon atoms with one atom off either of the inner 2 carbon atoms and 3 hydrogens off that one
- Chain of 3 carbon atoms with 2 carbon atoms off the central carbon atom, and 3 hydrogens off each one
What condition is needed for complete combustion
Excess oxygen
General equation for a complete combustion of alkanes
Alkane + Oxygen → Carbon dioxide + Water