C9.2 Fractional Distillation of Oil Flashcards
What type of hydrocarbons are the most useful and why?
Short chain molecules - because the ignite easily and burn well so they are good fuels
What are the differences between short-chain molecules and long-chain molecules in terms of temperature?
Short chains have lower boiling points
What is volatility?
The tendency to turn into a gas
What are the differences between short-chain molecules and long-chain molecules in terms of volatility?
Short chain have a higher volatility
What is viscosity?
How easily it flows
What are the differences between short-chain molecules and long-chain molecules in terms of viscosity?
Long chain have higher viscosity
What is fractional distillation?
When a mixture is separated into different liquids with similar boiling points called fractions
What type of hydrocarbons form at the bottom of the fractionating column?
Residue which is very thick - used to make roads and flat roofs with very high boiling points
What does the boiling point of a hydrocarbon depend on?
The size of the molecule
How does a fractionating column work?
The gases move up the column and the hydrocarbons condense when they react the temperature of their boiling points
The different fractions are collected as liquids at different levels
Where are the hydrocarbons with the lowest boiling points found?
At the cooler top part of the fractionating column
Why are shortchain hydrocarbons used as fuels?
Ignite more easily and burn well
With cleaner flames
