everchanging earth Flashcards
how much nitrogen is in today’s atmosphere?
78%
how much oxygen is in today’s atmosphere?
21%
how much argon is in today’s atmosphere?
0.9%
how much carbon dioxide is in today’s atmosphere?
0.04%
how did the earths first atmosphere form?
enormous volcanic activity errupting, releasing a mixture of toxic gases
what were the mixture of gases released?
methane
carbon dioxide
ammonia
water vapour
how were the seas and oceans formed?
the earth cooled and water vapour condensed to liquid
what is the test for hydrogen?
place a lit splint over the gas
popping sound if gas is present
what is the test for oxygen?
place a glowing splint over the gas
splint will relight if gas is present
what is the test for carbon dioxide?
bubble the gas through limewater
colourless limewater turns milky
describe what is used and released during photosynthesis?
uses carbon dioxide
releases oxygen
what happened to the poisonous ammonia released from volcanoes?
it decomposed on reacting with oxygen released from plants during photosynthesis
what is the gas that dissolved in the seas and oceans?
carbon dioxide
what happened to the carbon dioxide that dissolved in seas and oceans?
marine animals used the carbon atoms to make shells which created sedimentary rock such as limestone and chalk.
also fossil fuels were made by larger plants trapping carbon atoms
what are the 4 main sections of the earth?
crust
mantle
outer core
inner core