the condition of earth's atmosphere ar a particular time and place


envelope of gases surrounding earth, 78% nitrogen, 21% oxygen, 1% other gasses


21% of earth's atmosphere


78% of earth's atmosphere

carbon dioxide

plants need it to survive

water vapor

water in the form of a gas; invisible


forms when lightning interacts with oxygen in the air


form of oxygen which contains 3 oxygen atoms in each molecule instead of the usual two


gas needed for fire to burn


plants and animals use it to release energy from food

carbon dioxide

plants and animals give it off as waste product when they break down food to produce energy


contains oxygen and other gases that living things need


traps energy from the sun, which keeps the Earth's surface warm and Earth's water in liquid form, another requirement of living things


protects Earth from dangerous radiation from the sun and from meteoroids


makes up more of the air than any other gas


second most abundant gas in the atmopshere


plants and animals take this gas directly from the air and use it to release energy from their food

carbon dioxide

plants need this gas to make food

carbon dioxide

when cells of plants and animals break down food to produce energy, they give off this gas as a waste product

argon and carbon dioxide

make up most of the other 1% of the atmosphere

trace gas

refers to a gas or gases which make up less than 1% by volume of the earth's atmosphere

water vapor

not the same as steam, which is made up of tiny droplets of liquid water


dust, smoke, salt and other chemicles in the air

nitrogen, oxygen, argon, carbon dioxide

four most common gases in dry air

3 ways the atmosphere is important to life on Earth

1) contains oxygen for us to survive, 2) keeps the Earth's surface warm enough for water to exist as a liquid by trapping energy from the sun, 3) prevents Earth from being hit by most meteoroids

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