Fuels, Earth and Atmospheric Sciences Flashcards
what is Cyanobacteria and how did they contribute to the earths atmosphere
Cyanobacteria are some
of the earliest photosynthetic
organisms.
They live in shallow water.
Cyanobacteria and other organisms put more and more oxygen into the oceans, and some of this ended up in the atmosphere.
Over time, the amount of oxygen rose to its current levels.
what was the main gas in the atmosphere at the start
carbon dioxide
what did volcanos produce
lots of Co2
some methane, nitrogen, ammonia
water vapour
what metal compound shows that there was little oxygen in the atmosphere previously
Iron Pyrite
how do plants effect the amount of oxygen in the atmosphere
Plants need food to grow, and they release oxygen as they make food using photosynthesis. The spread of land plants increased the amount of oxygen in the atmosphere.
what percentage of oxygen makes up the earths atmosphere today
21%
What percentage of nitrogen and oxygen are in today’s atmosphere?
Nitrogen – 78%
oxygen - 21%
how carbon dioxide has decreased over time
Locked up in sedimentary rocks
Locked up in fossil fuels
Photosynthesis
Dissolved in the oceans
How is todays atmosphere different to before
Before:
there was mostly Carbon Dioxide
Some Water Vapour
Small amount Methane
Small amount Ammonia
Little to no oxygen
Now:
Carbon Dioxide 0.04%
Nitrogen 78%
Oxygen 21%
Noble Gases 0.01%
how is acid rain formed
the sulphur produced when burning fuels in cars, seep into the atmosphere and react with water in the clouds to produce acid rain
define a hydrocarbon
compound made purely of hydrogen and carbon
what is the formula for alkanes
CnH2n+2
what is the formula for alkenes
CnH2n
what is the test for an alkene
mix with bromine water, if the solution turns from yellow-orange to colourless
define a homologous series
a family with the same general formula and similar chemical properties
define a hydrocarbon
compounds containing hydrogen and carbon atoms only
what is an isomer
the same molecular formula but the different arrangement of atoms
what is a functional group
an atom or group of atoms within a molecule that has similar chemical properties whenever it appears in various compounds
what would the equation be for the complete combustion of methane
CH4 + 2O(2)= Co2 + 2H(2)O
what is the balanced equation for the complete combustion of ethene
C(2)H(4) + O2 = C0(2) + H2O
what is bromine water
aqueous bromine/ bromine dissolved in water
What are the six fractions of crude oil
Gases
Petrol
Kerosene
Diesel
Fuel
Bitumen
What are the six fractions of crude oil
Gases
Petrol
Kerosene
Diesel
Fuel
Bitumen