Alkenes and Polymers Flashcards
What is Organic Chemistry
The study of compounds containing carbon
What is cracking
The thermal decomposition of a long chained hydro-carbon into a short - chained hydrocarbon.
What is an alkene
A family of hydrocarbons with a general formula of CnH2n
What 3 characteristics does the homologous series have
Similar chemical properties
Trend in physical properties
Same general formula
What is the structural formula
e.g CH3CHCH3CH3
How does fractional distillation work
1) Crude oil is heated to make it a gas
2) Passed into the bottom of fractional distillation column
3) Lighter fractions condense at lower temperatures. Heavier fractions condense at higher temperatures.
4) The tower is hotter at the bottom and cooler at the top, so heavier fractions condense nearer the bottom and lighter ones at the top.
What is an isomer
A molecule that has the same molecular formula but different structure
Give all the crude oil products, starting from the top
Refinery gasses Gasoline (Petrol) Kerosene (aircraft fuel) Disel (Trucks) Fuel oil (Ships) Bitumen (Tar)
Alkenes are described as……..because they have…..carbon-carbon………bond, which means more hydrogen atoms can be……
Unsaturated
One
Double
Added
What is the displayed formula of propene
H
|
H - C = C - C - H
| | |
H H HIn what circumstances does an alkane react with bromine
It reacts if it is in the presence of UV light.
What is meant by substitution
A hydrogen atom in the alkane is replaced by a bromine atom
How does an alkene react with bromine
The double bond is broken and the bromine atoms are added. UV light is NOT NEEDED!
What is the Homologous series
A family of compounds that have similar chemical properties, a trend in physical properties but same general formula.
What does Saturated mean
An organic molecule with only single bonds
What does Unsaturated mean
An organic molecule with the presence of double bonds
What is an addition reaction
The breaking of a double bond and the bondings of other atop onto a molecule
What is the structural formula of Butane
CH3 CH2 CH2 CH3
What is the displayed formula of Butane
H H H H
| | | |
H-C-C-C-C-H
| | | |
H H H HWhat is the molecular formula of Butane
C4H10
Give the first 5 Alkanes
Methane Ethane Propane Butane Pentane
Methane + Oxygen =
Carbon dioxide + Water
Methane + Chlorine = = Chloro-methane + Hydrogen-chloride
UV
What is the symbol equation
CH4 + Cl2 = CH3 + HCl
What happens when an alkene react with Bromine
The double bond is broken and the bromine atoms are added. UV light is not required
Br Br
| | H-C=C -H + Br2 = H-C-C-H
| | | |
H H H H
What is in higher demand, long-chained hydrocarbons or short-chained hydrocarbons
Short-chained hydrocarbons
Cracking involves the…………of long chained alkanes into alkenes and shorter-chained alkenes using……. as a catalyst and a temperature in the range of……..
Thermal decomposition
Aluminium Oxide
600-700 degrees
What is a Monomer
Make up Polymers and have a double Carbon Carbon bond, so they are alkenes
Why is cracking an important part of the oil industry
- Higher demand for short chained hydrocarbons
- Long chained hydrocarbons are in surplus
- Cracking produces short chained hydrocarbons
- Alkenes are also produced which can be used in ethanol and to make polymers
How do you test for an alkene
Add to Bromine water and it will turn colourless
What is a fuel
A substance that when burned releases energy
