Hydrocarbons Flashcards
Define Saturated
No Double Bonds
Define Unsaturated
Has Double Bonds
What is the Alkene Test
Bromine Water
What is a positive indication of the Alkene test
Turns bromine water colourless
Aviation fuel is
kerosene
Viscosity - Short Chains
Not Viscous
Viscosity - Long Chains
Viscous
Boiling Points/Melting - Long Chains
High
Boiling Points/Melting - Short Chains
Low
What are the 3 properties of short hydrocarbons?
Volatile - low boiling point.
Runny - low viscosity (not thick & gloopy).
Flammable.
Why are the products of cracking useful?
Shorter hydrocarbons make better fuels.
Shorter alkenes can also be used as feedstock for the petrochemical industry to make polymers and detergents.
What happens to the volatility of alkanes as their chain length (number of carbon atoms) increases?
Alkanes become less volatile as chain their length increases.
Are alkenes saturated?
No, they are unsaturated as they have a carbon-carbon double bond.
Outline how catalytic cracking works.
Long chain alkanes are heated until they vaporise into a gas.
The gaseous alkanes are passed over a hot aluminium oxide catalyst.
This breaks the long chain alkanes into a shorter chain alkane and an alkene.
What does volatility mean?
Volatility refers to how easily a substance vaporises/evaporates into a gas.
