Organic Chemistry Flashcards
What is a hydrocarbon?
A compound made of only hydrogen and carbon ONLY
What type of bonding do hydrocarbons have
Covalent because they are both non-metals
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 general formula for a hydrocarbon
Cn+H2n+n
What is are isomers
compounds which have the same molecular formula but different structure
What type of bonds do alkanes have
Single
What is crude oil
A mixture of hydrocarbons which have different chain lengths and boiling points
Describe how fractional distillation separates crude oil into different fractions
The oil is heated until it is vaporised, it then goes into a fractioning column which is being heated. The hydrocarbons with longer chains have higher boiling points so ether are separated first. At the top of the column are hydrocarbons with shorter chains as they have lower boiling points.
What is incomplete combustion
Burning a hydrocarbon in a limited supply of oxygen
What is complete combustion
Burning a hydrocarbon in a unlimited supply of oxygen
What are the products of incomplete combustion
Soot - carbon and carbon monoxide
What are the products of complete combustion
Carbon Dioxide and water
What is a homogeneous series
A homologous series is a family of hydrocarbons with similar chemical properties who share the same general formula.
What are the types of oil found when crude oil is separated and their uses ( from top to bottom)
- refinery gasses: fuel for domestic heating and cooking
- petrol : fuel for cars
- kerosene : fuel for aircrafts
- diesel oil : fuel for some cars and trains
- fuel oil : fuel for ships and power stations
- bitumen : for roofs and roads
Trends found in crude oil fractions as you go up the column
As you go up:
- boiling point decreases
- length of chain
- volatility increases
- flow increases
- ignites easily
What does endothermic mean
Releases heat energy
Describe how nitrogen oxides are formed and why they are harmful to the environment
When car engines get too hot, nitrogen and oxygen in the air react and float up into the atmosphere (as it is a gas) and becomes dissolved in rain which causes acid rain which can damage aquatic life and is harmful to the environment
What does the term unsaturated mean
Has a double bond between carbons
What is cracking
The process of breaking down long hydrocarbon molecules into smaller chains
Alkenes are what kind of hydrocarbons
UNsaturated
What are alkenes
Hydrocarbons that have one (or more) double covalent bond therefore considered unsaturated. They are very reactive and undergo addition reactions across their double bond
General formula for alkenes
Cn H2n
what is the name of alkene with formula C2H4
ethene
what is the name of alkene with formula C3H6
propene
what is the name of alkene with formula C4H8
butene
alkenes react with bromine by addition reactions to form
dibromoalkanes
What is the colour change when alkenes react with bromine to form dibromoalkanes
orange/brown to colourless
Does bromine exist naturally in what state
a liquid (also DIATOMIC)
When alkAnes and bromine react under specific conditions, the reaction can be known as a ….. reaction
substitution reaction
What conditions are needed when steam reacts with alkenes
- 300*c
- 60-70 atm
- phosphoric acid catalyst
Why do alkenes decolourise bromine water
- bromine that was aq now bonded to carbon
What is a polymer
A polymer is a (large) molecule, made from joining together many small molecules called monomers
what is a monomer
a monomer is the small molecule containing the double bond that makes up the repeated pattern found in polymers (alkene)
What must a monomer have
- double bond between 2 carbons
What does the term biodegradable mean
Can be broken down by action of bacteria
Why is cracking a common industrial process
- because the demand for shorter hydrocarbons is much larger compared to longer chain hydrocarbons it is more efficient to crack hydrocarbons to make shorter ones that will be more useful
When burning plastic waste, what can happen that damages the environment
- the release of toxic gases into the atmosphere