Weathering

Question 1

Weathering:

Answer 1

Weathering is the breakdown of rock. Unlike erosion, the rock is broken apart but then remains where it is.

Question 2

Biological weathering:

Answer 2

Plants and trees often grow in the joints of rocks. As they grow, the roots get
larger and grow down into the rock. This breaks apart the surrounding rocks.

Question 3

Chemical weathering:

Answer 3

When water mixes with CO 2
in the air it becomes weak carbonic acid. This acid
will slowly dissolve alkaline rocks such as limestone and chalk

Question 4

Physical weathering

Freeze Thaw:

Answer 4

Water gets into a crack in
the rock. If the temperature drops below
freezing, the water will freeze and expand,
putting pressure on the rock around it.
When the water freezes and melts
repeatedly, the rock eventually falls apart.

Question 5

Onion-skin:

Answer 5

When rock is heated by the sun, the
outside layers of the rock will heat up and expand but
the inner part of the rock does not. When this
happens repeatedly from day to night-time, the outer
layers can break off from the rest of the rock.