How does the fractionating column separate crude oil?
- By colour, with the darkest at the top
- By boiling point, with the lowest boiling off highest
- By washing it through water tanks
How did crude oil form?
- Volcanoes melting rock last century
- Rivers drying out in summer heat
- Tiny sea life buried, cooked by heat and pressure
Long-chain fractions are thicker and harder to evaporate than short ones.
Circle one: True False
Cracking turns decane C10H22 into octane plus ethene. What shows this?
- Water plus carbon dioxide
- Methane only
- Octane C8H18 plus ethene C2H4
Why does petrol come off higher up the column than bitumen?
- Workers pump petrol in at the top
- Petrol chains are shorter with lower boiling points
- Bitumen floats above petrol vapours
What conditions crack a long hydrocarbon chain?
- Freezing with salt
- Heat with a catalyst
- Stirring with cold water
Fraction A flows like water and catches light fast. Fraction B is thick and stubborn. What are they?
- A is short-chained and B is long
- A is long-chained and B is short
- Chain length cannot be told this way
Why would a refinery break long molecules into shorter ones on purpose?
- Short fractions are wanted more than long ones
- Cracking makes crude oil form faster
- Long chains damage the column steel
Sorting and splitting crude oil W1-mt_Jg3O4EQ9Vz-s1
- By boiling point, with the lowest boiling off highest · Each fraction condenses at the level matching its boiling point.
- Tiny sea life buried, cooked by heat and pressure · Buried sea life cooked over millions of years into petroleum.
- True · More carbons mean stronger holds between molecules, so thick and slow.
- Octane C8H18 plus ethene C2H4 · One long chain splits into a shorter alkane plus an alkene.
- Petrol chains are shorter with lower boiling points · Short petrol chains boil low, so they rise high before condensing.
- Heat with a catalyst · Heat plus a catalyst snaps long chains into shorter ones.
- A is short-chained and B is long · Runny and flammable means short chains, while thick and stubborn means long.
- Short fractions are wanted more than long ones · Demand for petrol outruns demand for bitumen, so cracking rebalances supply.