half term 4- Rock cycle

Question 1

6 layers of the earth and their properties

Answer 1

• solid inner core: made from nickel and iron
• liquid outer core: made from nickel and iron
• mantle: properties of solid, but can flow very slowly, metal oxides
• lithosphere: cool, rigid brittle
• oceanic crust: thick
• continental crust: thick and rocky

Question 2

what is the layer of atmosphere nearest the earth and what are the mixture of gases?

Answer 2

troposphere, 78% nitrogen and 21% oxygen

Question 3

Nitrogen makes up 78% of the air, calculate the volume of nitrogen in a classroom of volume 250m3

Answer 3

250x0.78=195m3

Question 4

a 400m3 sample of air contains 84m3 of gas X. calculate the percentage of the air that is gas X.

Answer 4

84/400=0.21

0.21x100=21%

Question 5

properties of intrusive rocks

Answer 5

• large crystals

- cooled slowly underground

Question 6

properties of extrusive rocks

Answer 6

• small crystals

- cooled quickly on the surface

Question 7

how are sedimentary rocks formed?

Answer 7

erosion breaks up the rocks and weathering moves the bits away. these grains are fixed together by cementation and compaction. all the water is squeezed out from between the rocks and sticky crystals that cements rock pieces together is formed, sedimentation
could take millions of years

Question 8

how are metamorphic rocks fomed?

Answer 8

made from other rocks changed from heat or pressure
earth movements can cause rocks to be deeply buried or squeezed, so rocks are heated and put under great pressure
they don’t melt but the minerals they contain are changed chemically

Question 9

two examples of sedimentary rock

Answer 9

limestone and chalk

Question 10

two examples of metamorphic rock

Answer 10

marble and slate

Question 11

two examples of igneous rock

Answer 11

granite and basalt

Question 12

which types of rock contain layers

Answer 12

sedimentary

metamorphic- thin layers

Question 13

three types of rock in order from softest to hardest

Answer 13

sedimentary, metamorphic, igneous

Question 14

what type of grains are all the rock types made of?

Answer 14

sedimentary- small grains weakly help together
metamorphic- small crystals
igneous- randomly arranged interlocking crystals. these can be big if intrusive or small if extrusive

Question 15

what is the one porous type of rock?

Answer 15

sedimentary

Question 16

how is igneous rocks formed?

Answer 16

molten rock forms when rocks melt. the molten rock is called magma. when this cools and solidifies igneous rock is formed.

Question 17

which types of rocks contain fossils?

Answer 17

sedimentary

metamorphic- twisted fossils

Question 18

weathering

Answer 18

process that breaks rocks down

Question 19

deposition

Answer 19

small pieces of rock fall to the riverbed or seabed when the current slows down

Question 20

erosion

Answer 20

soil and rock particles are worn away and moved elsewhere by wind, water or ice

Question 21

compaction

Answer 21

layers of sediments are squashed by more layers on top of them

Question 22

magma

Answer 22

molten rock under the earth’s surface

Question 23

metamorphose

Answer 23

change from one type of rock to another

Question 24

lava

Answer 24

molten rock on top of the earth’s surface

Question 25

4 types of weathering and info about them

Answer 25

• biological weathering: when tree grows into joints, widens and breaks of pieces of rock. and burrowing animals create undercuts and widen joints.
• chemical weathering: acid rain or rain water is capable of dissolving some carbonate rocks.
• freeze-thaw activity: water penetrates joints, cleavages, faults and pore spaces. water turns to ice and expands, cracks the rock
• onion skin weathering (exfoliation): common in area with large temperature ranges. outer layer of rock heats and expands more rapidly than inner layers during the day. at night outer layers contract more rapidly than the depth. a series of concentric fractures are initiated and the rock peels off in layers like an onion.

Question 26

what is the difference between weathering and erosion?

Answer 26

• weathering is a long process but erosion is a short process
• in weathering there is no movement in sources but in erosion movement occurs followed by deposition at a new place
• erosion has many more types than weathering

Question 27

what rock is made from shale?

Answer 27

basalt

Question 28

what rock is made from limestone?

Answer 28

marble

Question 29

how do metamorphic rocks differ from sedimentary rocks?

Answer 29

• metamorphic rocks are rocks that have changed from one type of rock to another. while sedimentary rock is formed from sediments
• sedimentary rocks are formed in the earth surface, while metamorphic rocks are formed deep in the earth.

Question 30

what are the properties of sedimentary rock?

Answer 30

• contains layers
• contains fossils
• small grains weakly held together
• porous
• soft

Question 31

rock cycle

Answer 31

the relationships between different types of rock and the processes that occur to change these over long periods of time

Question 32

uplift

Answer 32

upwards movement of the earth’s surface in response to natural processes such as earthquakes