Igneous Rocks - 8.2 Weathering

Question 1

What is weathering?

Answer 1

The physical and chemical processes that break rocks down.

Question 2

What can cause physical weathering?

Answer 2

-Temperature change
-The action of water and ice
-crystallisation of salts
-wind
-living plants

Question 3

What can cause chemical weathering?

Answer 3

-Gases
-Acids
-Water

Question 4

What is physical weathering?

Answer 4

Something that physically breaks apart a rock.

Question 5

What is chemical weathering?

Answer 5

The process where water and chemicals in the water and air react with a rock and change it.

Question 6

How does temperature change affect a rock?

Answer 6

Due to solids expanding when they are heated and contracting when they are cooled rocks can be broken down, if temperature changes rapidly the expanding and contracting can crack the rock in several places.

Question 7

How does ice weather rocks?

Answer 7

Ice can break down rocks by widening cracks that are already there, this happens because of the water trapped in the rocks that freeze.

Question 8

How do glaciers weather rocks?

Answer 8

Glaciers are like frozen rivers, as they move they slowly scrape away rocks surrounding and this can form valleys.

Question 9

How does water weather rocks?

Answer 9

Due to some waters constant movement by smashing or washing past a rock the water can weather the rock away, for example waves that weather rock faces.

Question 10

How does the crystallisation of salts weather rocks?

Answer 10

Inside water there is usually salts like sodium chloride. When water gets trapped in rocks and the water evaporates the salt is left to crystallise inside the rock and this can break the rock apart.

Question 11

How does wind weather rocks?

Answer 11

Small particles carried in the wind can blast the rock surface and weather pieces away.

Question 12

How do living plants weather rocks?

Answer 12

As plants grow tree roots can slowly seep through cracks or make their own and as the tree grows the cracks can be split as well.

Question 13

How do gases weather rocks?

Answer 13

In the air carbon dioxide and oxygen can react with certain types of rocks and change the chemicals in the rocks to not hold together as strongly and make it crumble.

Question 14

How do acids weather rocks?

Answer 14

Rainwater contains dilute acids that can attack rock. These acids naturally form in the air during lightning or pollution can form the acids in the air, when rain falls it can be called acid rain.

Question 15

How does water chemically weather rocks?

Answer 15

Some rocks have soluble materials in them so they can be broken apart with running water after the soluble materials are dissolved.

Question 16

What is erosion?

Answer 16

The process where small particles of rocks broken off by weathering are carried away by wind water or ice.

Question 17

Where are the most common places for weathering to occur?

Answer 17

Mountains or hills this is because gravity makes water move more rapidly down a slope than on level ground.

Question 18

What is deposition?

Answer 18

The process where eroded rock particles are deposited.

Question 19

How does deposition occur?

Answer 19

This process occurs usually where moving water, wind or ice slow down. In rivers it is in the bends, on these parts larger particles are deposited because the river is slowed down.

Question 20

Where does the eroded material go if it is still flowing in the river when it gets to a lake or sea?

Answer 20

If the material is still in the river by the time the river makes it to the sea or a lake it settles to the bottom and build up over time.