Organic Chemistry Flashcards
What is the order of a fractional distillation column from cool at the top to hot at the bottom?
- Refinery gases
- Petrol
- (Naptha)
- Kerosene
- Diesel
What are some qualities of refinery gases compared to other hydrocarbons?
- Least viscous
-Most flammable
-Most volatile
-Lightest in colour
-Low boiling point
-Smallest molecules
What are some qualities of bitumen compared to other hydrocarbons?
- Most viscous
-Least flammable
-Least volatile
-Darkest in colour
-High boiling point
-Largest molecules
What is a hydrocarbon?
A substance made of only carbon and hydrogen, obtained by the fractional distillation of crude oil
What is fractional distillation?
The separation of liquids by boiling point
Describe how fractional distillation produces fuel oil from crude oil.
- Crude oil is vaporised
-Vapour travels up the column
-Column is hot at the bottom and cool at the top
-As the vapour travels, the fractions condense at different heights - according to their boiling points
What is a homologous series?
A ‘family’ of organic compounds that share a functional group and therefore have similar features and chemical properties
Give some features of a homologous series.
- Same general formula and functional group
-Trend in boiling points
-Similar chemical reactivity
What are isomers?
Molecules with the same molecular formula but a different structural formula (same number and type but different positions, e.g Butane and 2-Methylpropane)
What occurs in an addition reaction?
The double bond breaks and a new atom is added to each C atom
What is a fuel?
a substance which can be burned to produce heat energy
What are the products of complete combustion?
carbon dioxide and water
What are the products of incomplete combustion?
carbon monoxide, carbon and water
What is cracking?
The thermal decomposition (600-700*C) of long-chain hydrocarbons in the presence of a catalyst e.g alumina/silica
Why is cracking useful?
It breaks down long-chain hydrocarbons into smaller hydrocarbons and alkenes, which are more useful and sought-after
What is the general formula of an alkane?
CnH2n+2
What is the general formula of an alkene?
CnH2n
Why are alkanes saturated hydrocarbons?
They contain only single bonds
Why are alkenes unsaturated hydrocarbons?
They contain double bonds between carbon atoms
How do alkanes react with halogens in the presence of UV radiation?
Will burn and react
What does bromine water test for?
Double bonds (alkenes)
What is an addition polymer?
Many small molecules called monomers joined together
GIve some problems in the disposal of addition polymers.
-Inertness and inability to biodegrade
-production of toxic gases when burned
