earth and atmosphere

Question 1

what is the approximate proportion of nitrogen in earths current atmosphere

Answer 1

80%

Question 2

what is the approximate proportion of oxygen in earths current atmosphere

Answer 2

20%

Question 3

there are small proportions of water vapour noble gases and which other gas in earths current atmosphere

Answer 3

carbon dioxide

Question 4

what was formed when shells of organisms made using dissolved carbon dioxide fell to the bottom of the ocean and were covered and compressed

Answer 4

sedimentary rock

Question 5

name three types of rock

Answer 5

igneous
metamorphic
sedimentary

Question 6

how is igneous rock formed

Answer 6

the cooling of molten rock (magma)

Question 7

how are metamorphic rocks formed

Answer 7

formed from another rock under heat and pressure

Question 8

this describes rocks being broken up by the roots of plants or animals borrowing into them

Answer 8

biological weathering

Question 8

what is weathering

Answer 8

the process of breaking down rocks into smaller pieces

Question 9

this describes rocks being broken up because substances in rainwater rivers and seawater or the air react with minerals in the rocks

Answer 9

chemical weathering

Question 10

this describes rocks being broken up by changes in temperature freezing and thawing of trapped water or the action of waves and rivers

Answer 10

physical weathering

Question 11

what is a fossil

Answer 11

is the preserved remains or traces of an organism

Question 12

define erosion

Answer 12

erosion is the breaking down and movement of rocks from one place to another it is sometimes called transportation

Question 13

how can C02 be removed from our atmosphere

Answer 13

photosynthesis

Question 14

what are the processes that release carbon dioxide into our atmosphere

Answer 14

combustion of fossil fuels
respiration by plants and animals
decomposition of plants and animals