Air and Water Flashcards
When did the earth form?
4.6 billion years ago
what is the most plentiful gas in the atmosphere today and what percentage of the atmosphere is it?
N2 - 78%
what is the second most plentiful gas in the atmosphere today and what percentage of the atmosphere is it?
O2 - 21%
How is carbon monoxide caused?
incomplete combustion in a shortage of O2
how can you reduce polluting Carbon Monoxide?
converted to CO2 by a catalytic converter
how can you reduce sulfur dioxide?
remove from power stations by capturing with limestone
what is sulfur dioxide caused by?
burning coal or petrol containing sulfur in oxygen
what are oxides of nitrogen caused by?
from N2 and O2 at very high temps such as in an engine
how do you reduce oxides of nitrogen?
convert to N2 with a catalytic converter
Reasons why CO2 in the atmosphere decreased
earth cooled so oceans condensed so CO2 dissolved into them
photosynthesis (CO2 in bodies of planst and animals eat them, now as glucose)
trapped as sediment
ocean creatures making shells out of calcium carbonate
how did the CH4 and NH4 in the atmosphere reduce?
they reacted with the O2 caused by plants photosynthesizing
name some sedimentary carbonate rocks
chalk,limestone
when the earth was young what was the main gas?
CO2
which planets have atmosphres like young earth?
venus, mars
where did all the nitrogen come from?
the ammonia that reacted with o2 from photosynthesis
why does deforestation lead to increased co2?
plants no longer photsynthesize
burned logs release co2
why can radiation from the sun pass through the atmosphere?
it has a short wavelength
what types of radiation do atmospheric gases absorb?
outgoing long wavelength radiation
what is the formula for methane?
CH4
where does methane come from in modern times?
decomposition of rubbish in landfill, animal farming
in the burning phosphorous experiment, why does the level of water in the jar go up while the rest does not?
there’s more pressure inside the jar
what is the scientific word for drinkable, and how is it different from distilled water?
potable water is different as it contains minerals that distilled does not contain
what are the processes in processing water?
screening, sedimentation, filtration,sterilisation
what is sedimentation?
letting sediment float to the bottom
what chemical is used in what process while processing water?
chlorine used in sterilisation to kill bacteria
what sort of countries operate desalination plants?
hot, dry countries by the sea (solar energy is a plus)
what do desalination plants use?
reverse osmosis
why does sulphur dioxide cause limestone erosion?
the sulphur dioxide dissolves in rain to become sulphuric acid, then causes acid rain which reacts with the calcium carbonate of the limestone to erode it
how is natural gas formed?
heat and pressure make bodies of animals and remnants of plants which contain co2 which came from photosynthesis into natural gas
