Fuels and Earth Science Flashcards
How is crude oil separated
Fractional distillation in a fractionating column
How does fractional distillation work
A gradient of boiling points so the longer hydrocarbons with higher boiling points are at the bottom
What is made in each fraction
1 - liquified petroleum and refinery gases
2 - chemicals used in household
3 - petrols for vehicles
4 - jet fuel
5 - diesel fuel
6 - lubricating oils, waxes and polishes
7 - fuels for ships
8 - bitumen for roads
Why do longer hydrocarbons have higher boiling points
Stronger intermolecular forces
What is formed when hydrocarbons undergo complete combustion
Carbon dioxide + Water
What is formed when hydrocarbons undergo incomplete combustion
Carbon
OR
Carbon monoxide
AND
Water
What can C and CO do
CO
Stop red blood cells from carrying oxygen and lead to a lack of oxygen
C
Carbon can build up and deposit themselves and cause respiratory issues
What does sulfur dioxide cause
Acid rain which can cause lakes to become acidic and erosion and corrosion of things
What is cracking
The splitting up of long-chain hydrocarbons
Turning alkanes into smaller alkanes and alkenes
What are the conditions for cracking
400-700 degrees
70 atm
Aluminium oxide used as a catalyst
Why is cracking useful
Allows matching of supply and demand
How much of each element is there in the air
N2 - 78%
O2 - 21%
Ar - 0.1%
CO2 - 0.04%
Stages of the atmosphere
1 - Volcanoes gave out CO2 and steam
2 - Nitrogen in atmosphere increased by ammonia reacting with oxygen. The amount of oxygen in the air increased and CO2 dissolved in the ocean
3 - Build up of O2 killed off early organisms and allowed the evolution of more complex beings
How have humans changed the composition of air
More demand means that more fossil fuels have been burnt, releasing more CO2 into the atmosphere
CO2 is also released into the atmosphere via deforestation and volcanoes erupting
Explain the greenhouse effect
The earth absorbs some of the IR radiation in the form of heat and radiates some back
Greenhouse gases absorb this and re-emit it back towards earth and space
This keeps the earth warm
