Organic Chemistry Flashcards
What is Crude oil?
It is a oily mixture made up of different Hydrocarbons
What are Hydrocarbons?
A compound made up of Hydrogen and Carbon atoms only.
Alkanes are a type of what?
Hydrocarbon
What is the main feature of Alkanes?
They have a single covalent bonds between the carbon atoms
Because Alkanes have a single covalent bond between carbon atoms what does it mean?
They are saturated
What is the General formula of Alkanes?
Cn + H2n+2
How many carbon atoms does Methane have?
1
How many carbon atoms does Propane have?
3
How many carbon atoms does Betane have?
4
How many carbon atoms does Ethane have?
2
What are Saturated Compounds?
they only have single bonds
What is Incomplete combustion?
is a combustion reaction in which there is not enough oxygen for the fuel to burn completely.
What is Incomplete combustion?
Is a combustion reaction in which there is not enough oxygen for the fuel to burn completely.
What is Complete combustion?
is when a fuel burns completely in excess oxygen to produce Carbon dioxide + Water.
What is the reaction of Complete combustion of Hydrocarbons?
Hydrocarbon + Oxygen – Carbon dioxide + Water
What is the reaction of Incomplete combustion of Hydrocarbons?
Hydrocarbon + Oxygen – Carbon monoxide + Water
Name 5 symptoms of Carbon Monoxide?
Blurred vision Weakness Dizziness Vomiting Shortness of breath
What is the smell of Carbon monoxide?
It is Odourless
What is the color of Carbon monoxide?
Colourless
What is Viscosity of a liquid?
It is how runny a liquid is which affects how quickly it flows
A liquid with low viscosity means what?
Runny
A more viscous liquid means what?
Less runny
The shorter the Hydrocarbon means what in terms of Viscosity?
The more runny the Hydrocarbon is.
What are Intermolecular forces?
The forces between the individual molecules of a substance which are weak.
What is a Covalent bond?
The bonds between atoms within a molecule which are very strong.
Do shorter chain Hydrocarbons have high or low boiling points
Lower boiling points
Why do shorter chain Hydrocarbons have lower boiling points?
because they are a shorter molecule meaning their are fewer intermolecular forces between each molecule meaning less heat energy is needed to overcome the forces
Why do longer chain Hydrocarbons have higher boiling points?
because they are a longer molecule meaning their are more intermolecular forces between each molecule meaning more heat energy is needed to overcome these forces
What state is Ethane at room temperature?
Gas
What state is Hexane at room temperature?
Liquid
What is Crude oil separated by?
Fractional distillation
How does Fractional distillation work?
1) The Oil is heated at the bottom of the column it till it is turned mostly into a gas
2) It gets cooler as you go to the top
3) The longer Hydrocarbons have high boiling points so they condense back to a liquid and drain out the column early on when they are near the bottom.
4) The shorter Hydrocarbons have lower boiling points so they condense and drain out much later on near the top of the column where its cooler.
5) Then the oil is separated into different fractions having similar properties.
Name in order from Coolest to the hottest uses of fuels that is produced from crude oil in Fractional distillation.
Petrol Kerosene Disel oil Heavy fuel oil Bitumen
What does flammable mean?
easy to set on fire
The shorter the Hydrocarbon what does it mean in terms of flammability?
More flammable
The longer the Hydrocarbon what does it mean in terms of flammability?
less flammable
Name 2 problems with separated crude oil.
Short chain hydrocarbons are flammable meaning they make good fuels
Long chained hydrocarbons are not useful
What is Cracking?
Splitting up Long chain hydrocarbons to make them useful
What does Cracking involve?
1) Heat the long chain hydrocarbons to vapourise them(turn into gas)
2) Then the vapour is passed over a hot powered aluminium oxide catalyst.
3) The long chain molecules split apart on the surface of the speaks of the catalyst.
What are long chain Hydrocarbons used for?
Polymers(Plastics)
What are unsaturated hydrocarbons?
They have at least one carbon to carbon double bond .
What are Alkenes?
They are unsaturated hydrocarbons have at least one carbon to carbon double bond .
What are Alkanes?
They are saturated hydrocarbons that have at least one carbon-carbon single bond so no more hydrogen atoms can be added
Are alkenes more reactive than Alkanes?
Yes
What is the test for Alkenes?
Bromine water, alkenes will decolourise bromine water alkanes do not.
What type of reaction is Cracking?
Thermal decomposition reaction
What is Thermal decomposition?
Breaking molecules down by heating
Name two methods of cracking.
Catalytic cracking ( we use heat and a catalyst) Steam cracking (we use heat and steam)
