Unit 4 - Lesson 6: Crude Oil Flashcards
What is crude oil a mixture of?
Crude oil is a mixture of hydrocarbons.
Coal, natural gas and crude oil are all what?
Fossil fuels.
What are hydrocarbons made of only?
Carbon and hydrogen.
What is crude oil made from? How is it made?
Crude oil is made from living things that died millions of years ago in the sea. They were gradually covered in layers of sediment. Under high pressure and heat, they turned to crude oil.
Is crude oil considered renewable or non-renewable? Why?
It’s considered non-renewable because it takes millions of years to remake. Crude oil is finite.
What does it mean when I say “crude oil is finite”?
Crude oil is finite (will run out if we keep using it at this rate).
What process is used to separate crude oil into useful products in an oil refinery?
Fractional distillation.
Crude oil is separated into useful products in an oil refinery using fractional distillation. What do we call these useful products?
Fractions.
What do ‘fractions’ (useful products) contain?
Hydrocarbon chains of similar length.
What are fractions separated in?
A fractionating column.
When defining a hydrocarbon in your exam, what word should you make sure to write before ‘carbon and hydrogen’?
Hydrocarbons are made of ONLY carbon and hydrogen.
What are refinery gases often used as?
Liquified petroleum gas (LPG).
What is LPG used for?
LPG is used for heating homes and cooking.
What is LPG a mixture of?
Methane, ethane, propane and butane.
Can refinery gases be separated into these products (methane, ethane, propane and butane) if needed?
Yes.
Draw a fractionating column that begins with refinery gases and ends with bitumen. Label what each gas is used for and give the temperatures for the beginning and ending.
https://i.pinimg.com/736x/05/f4/e3/05f4e361aaccef3e6cff65655929835f.jpg
What is the mnemonic for a crude oil fractionating column?
Lazy Penguins Keep Drinking Hot Beer.
LPG, Petrol, Kerosene, Diesel, Heavy Fuel Oil, Bitumen.
Give the uses of these gases/fuels:
(a) LPG
(b) Petrol/Gasoline
(c) Kerosene
(d) Diesel
(e) Heavy Fuel Oil
(f) Bitumen
(a) Heating homes & cooking
(b) Fuel for cars
(c) Aircraft fuel
(d) Fuel for cars, lorries & buses
(e) Fuel for ships and power stations
(f) Bitumen for roads & roofs
What temperature is the bottom of the fractionating column for crude oil?
400 Degrees Celsius.
What temperature is the top of the fractionating column for crude oil?
25 Degrees Celsius.
Are the crude oils at the bottom of the fractionating column large or small molecules? What properties do they share?
They’re large molecules.
- High boiling points
- Not very volatile
- Doesn’t flow easily
- Doesn’t ignite easily
Are the crude oils at the top of the fractionating column large or small molecules? What properties do they share?
They’re small molecules.
- Low boiling points
- Very volatile
- Flows easily
- Ignites easily
Before entering the fractionating column, (WHAT) is done to the crude oil until the majority is turned into a (WHAT)?
Before entering the fractionating column, the crude oil is HEATED until the majority is turned into a VAPOUR.
Which end of the column is cooler? Is there a temperature gradient?
The top.
There is a temperature gradient; the top of the column is cooler than the bottom.
What happens to the gas as it rises?
It cools and condenses when it reaches a temperature just below its boiling point.
Through (WHAT) does the liquid fraction pour out of the column?
Through a CONDENSER, the liquid fraction pours out of the column (is separated).
Do short hydrocarbons have lower or higher boiling points than long hydrocarbons?
Short hydrocarbons have lower boiling points than long hydrocarbons.
Short hydrocarbons have lower boiling points than long hydrocarbons. Do they condense higher up or lower down the column?
They condense higher up the column.
The boiling point is also the (WHAT) point for crude oils?
The boiling point is also the CONDENSATION point.
What state do refinery gases stay in and why?
Refinery gases stay in a gas state because the temperature never gets low enough to condense.
Why does bitumen never turn to gas?
Bitumen has such a high boiling point that it never turns to gas. It’s the crude oil that couldn’t be vaporised. It pours out the bottom of the column.
Explain how the fractional distillation of crude oil works.
Before entering the column, the crude oil is HEATED until the majority is turned into a VAPOUR. The TOP OF THE COLUMN IS COOLER THAN THE BOTTOM. We say there’s a temperature gradient. As the gas rises, it cools, and CONDENSES when it reaches a temperature just below its boiling point. The LIQUID fraction pours out of the column (is separated) through a CONDENSER. Short hydrocarbons have LOWER BOILING POINTS than long, so they CONDENSE HIGHER UP THE COLUMN. The BOILING POINT is also the CONDENSATION POINT. Refinery gases stay in a gas state because the temperature never gets low enough to condense. Bitumen has such a high boiling point that it never gets turned to gas. It’s the crude oil that couldn’t be vaporised. It pours out the bottom of the column.
Fractions at the top of the column are SMALLER or BIGGER hydrocarbon chains?
Fractions at the top of the column are SMALLER hydrocarbon chains.
What are hydrocarbons? So, if you burn them, what do they release?
Fuels, so if you burn them, they release heat energy.
Do smaller hydrocarbons burn easier? Why or why not? What do we say smaller hydrocarbons are more due to this?
Yes, smaller hydrocarbons burn easier because the INTERMOLECULAR FORCES between molecules are weaker. We say they are more COMBUSTIBLE.
(Short/Long) molecules have (stronger/weaker) intermolecular forces. (More/Less) energy is required to break them.
(Short/Long) molecules have (stronger/weaker) intermolecular forces. (More/Less) energy is required to break them.
SHORT molecules have WEAKER intermolecular forces. LESS energy is required to break them.
LONG molecules have STRONGER intermolecular forces. MORE energy is required to break them.
Are shorter fractions more or less volatile?
Shorter fractions are MORE volatile.
Do shorter fractions evaporate easily or not?
Shorter fractions evaporate easily.
What colour and texture is crude oil? How does the colour and texture of crude oil change?
It’s black and viscous (tar-like). As the hydrocarbon chain of a fraction gets shorter, its colour gets lighter and viscosity decreases.
Finish these sentences:
(a) The shorter the chain length, the (MORE/LESS) combustible.
(b) The lower the boiling point, the (MORE/LESS) volatile (how easy it turns to vapour).
(c) The chain length (INCREASES/DECREASES) lower in the fractionating column.
(d) The colour gets (LIGHTER/DARKER) lower in the fractionating column.
(e) The boiling point (DECREASES/INCREASES) lower in the fractionating column.
(f) The viscosity (DECREASES/INCREASES) lower in the fractionating column.
(a) The shorter the chain length, the MORE combustible.
(b) The lower the boiling point, the MORE volatile.
(c) The chain length INCREASES lower in the fractionating column.
(d) The colour gets DARKER lower in the fractionating column.
(e) The boiling point INCREASES lower in the fractionating column.
(f) The viscosity INCREASES lower in the fractionating column.
Draw a diagram for distilling crude oil. Include the labels: Gasoline (petrol), Naphtha, Kerosene, Diesel Oil, Fuel Oil, and Bitumen Residue. Include the properties of the crude oils at either end of the fractionating column.
https://i.pinimg.com/736x/83/f4/ab/83f4ab37a158e0a729162e8fd073685a.jpg
