Organic Chemistry l Flashcards
What are the fractions of crude oil?
(Low BP to High BP)
Refinery Gases
Gasoline
Kerosine
Diesel
Fuel Oil
Bitumen
(Rich, Girls, Kiss, Dumb, Football, Boys)
What are Refinery gases used for?
Heating and cooking
What is Gasoline used for?
Cars
What is Kerosene used for?
Planes
What is Diesel used for?
Lorries
What is Fuel Oil used for?
Ships
What is Bitumen used for?
Tarmac
What is a hydrocarbon?
An compound made up of only hydrogen atoms and carbon atoms
How does Fractional Distillation work?
- Heated crude oil vapours enter the column
- Vapours rise until they reach their boiling boing, when they condense
- Different vapours condense at different heights due to their different boiling points
- Similar vapours condense together as a fraction
What are the temperatures for each fraction?
Refinery Gases - -50
Gasoline - 50-100
Kerosene - 180-220
Diesel - 220-250
Fuel oil - 250-350
Bitumen - 350+
What are the chain lengths for each fraction?
C1 - C4
C5 - C10
C10 - C16
C14 - C20
C50 - C70
C70+
What is the general formula for alkanes?
CnH2n+2
What is the formula for Methane?
CH4
What is the formula for Ethane?
C2H6
What is the formula for propane?
C3H8
What is the formula for Butane?
C4H10
What is the formula for pentane?
C5H12
What are isomers?
Isomers are molecules with the same molecular formula but different displayed formula
What are the characteristics of homologous series?
Similar chemical properties
Trends in physical properties
Same general formula
What is empirical formula?
Simplest whole number ratio
When does complete combustion occur?
When there is an excess of oxygen
What are the products of complete combustion?
Carbon dioxide and Water
When does incomplete combustion occur?
When there is not enough oxygen
What are the products produced in incomplete combustion?
What are the dangers of incomplete combustion?
Carbon Monoxide (CO)
- A toxic gas
- Attaches to haemoglobin and lower oxygen carrying capacity of blood
Soot (C)
- causes lung disease
What are the three pollutants released in the combustion of alkanes and what are the dangers?
Carbon dioxide
Greenhouse gas, traps heat in the atmosphere and causes global warming
Nitrogen Oxides
When nitrogen from the air combusts
Forms acid rain which is harmful to aquatic life and plants
Sulphur dioxide
Sulphur impurities in the fuel combust
Dissolves in rainwater to form acid rain
What happens when Halides react with Alkanes?
- Substition reaction - H is swapped with Br
- The reaction requires UV light
What is cracking?
A long chain of alkanes are broken down to produce smaller chains of alkanes
Why is cracking important?
Shorter chains are more useful
Shorter chains are in demand and supply is limited
What are the conditions for cracking?
Temperature - 650C
Catalyst - Aluminium Oxide
What is the general formula for alkenes?
CnH2n
What are unsaturated molecules?
Molecules contains double bonds
What are saturated molecules?
Molecules containing single bonds between carbon atoms
Formula for…
Ethene
Propene
Butene
Pentene
C2H4
C3H6
C4H8
C5H10
Describe the reaction between Br and alkenes
- Bromine is an orange/yellow solution
- Shake solution with bromine
- Mixture turns orange to colourless in the presence of an unsaturated molecule (alkene)
- Addition Reaction
- Does not need a UV light because alkenes are more reactive than alkanes
what is a polymer?
A polymer is a long chain of molecule made up of monomers
What is a monomer?
A monomer is a small reactive alkene
What is addition polymers?
Molecules with C=C bonds add into long chains
What are the four common polymers?
Poly(ethene)
Poly(propene)
Poly(chloroethene)
Poly(tetrafluoroethene)
What are the uses and properties of poly(ethene)
Properties
- electrically insulating
- flexible
Use
- Plastic bottles
- Plastic bags
What are the properties and uses of Poly(propene)?
Properties
- strong
- flexible
Uses
- Climbing Ropes
- Storage boxes
What are the properties and uses of Poly(chloroethene)?
Properties
- Long-Lasting
- Tough
Uses
- Wire insulation
- Drain pipes
What are the properties and uses of Poly(tetrafluoroethene) ?
Properties
- tough
- non stick
- resistant to high temp
Uses
- Non-stick coating
What are the four disposal options polymers?
- Re-use it
- Recycle
- Incinerate/destroy
- Landfill
Test for Alkane
- Add Bromine water and shake
- Under UV light
- Orange — colourless
Testing for alkene
- Add bromine water and shake
- Orange — colourless
Type of reaction with an alkane and bromine
Substitution
Type of reaction with an alkene and bromine
Addition