Organic Chemistry Flashcards
What is an organic compound?
Something that contains carbon atoms
How did crude oil form?
From the remains of dead animals and plants millions of years ago
What is crude oil a mixture of?
Hydrocarbons
What is a hydrocarbon?
Molecules made up of hydrogen and carbon atoms only
What is an alkane?
A saturated hydrocarbon
What is the general formula for an alkane?
CnH2n+2
What is a saturated hydrocarbon?
Contains only single covalent bonds between atoms
What is displayed formula?
Represents the covalent bonds present in a molecule as it lines
How do we name alkanes?
Look at the carbon chain length, apply the right prefix and add ‘ane’ on the end
What is the prefix for one carbon?
Meth-
What is the prefix for two carbons?
Eth-
What is the prefix for three carbons?
Prop-
What is the prefix for four carbons?
But-
How are the hydrocarbons in crude oil separated?
Fractional distillation
What is a fractional distillation ‘fraction’
Contains molecules with a similar number of carbon atoms
Describe temperature changes in the fractional distillation column
Hotter at the bottom, colder at the top
Why do the different fractions condense at different temperatures?
Different chain lengths have different boiling points
What are the two physical changes involved in fractional distillation?
Evaporation and condensation
What can crude oil fractions be used for?
Fuels as a raw material for the petrochemical industry
What different fuels come from crude oil?
Petrol, diesel, kerosene, heavy fuel oil, petroleum gases
What substances are made from crude oil, other than fuels?
Solvents, lubricants, polymers, detergents
What properties are affected by hydrocarbon chain length?
Boiling point, viscosity, flammability
How does hydrocarbon chain length affect boiling point?
The longer the chain, the higher the boiling point
What is flammability?
How easily a substance ignites or burns
How does hydrocarbon chain length affect the flammability?
The longer the chain, the less flammable it is
What is viscosity?
How thick a liquid is
How does hydrocarbon chain length affect viscosity?
The longer the chain length, the more vicious it is
Why do we burn hydrocarbon fuels?
To release energy
What type of reaction is combustion?
Oxidation
What are the two products when a hydrocarbon undergoes complete combustion?
Carbon dioxide, water
What is cracking?
Breaking down large hydrocarbons to smaller, more useful molecules
Why are smaller hydrocarbons more useful than larger molecules?
Make better fuels