Science U1 L2

Question 1

physical weathering

Answer 1

the process by which rock is broken down into smaller pieces by physical changes

Question 2

weathering

Answer 2

breakdown of rock material by physical and chemical processes

Question 3

what are agents of physical weathering?

Answer 3

1. temperature changes
2. pressure changes
3. plant and animal actions
4. water
5. wind
6. gravity

Question 4

exfoliation

Answer 4

process by which the outer layers of rock slowly peel away due to pressure changes

Question 5

abrasion

Answer 5

breaking down and wearing away of rock material by mechanical action of other rock

Question 6

chemical weathering

Answer 6

breakdown of rocks by chemical reactions

Question 7

Name two agents of chemical weathering.

Answer 7

oxygen in the air

acids

Question 8

oxidation

Answer 8

process by which other chemicals combine with oxygen

Question 9

acid precipitation

Answer 9

rain, sleet, or snow that contains a high concentration of acids

Question 10

what type of weathering is acid precipitation an agent of ?

Answer 10

chemical weatherin

Question 11

gradual wearing away of breaking down of rocks by abrasion is a type of what weathering?

Answer 11

physical weathering

Question 12

Ice Wedging

Answer 12

water enters a crack in a rock
the water turns into ice and expands
this increases the size of the crack

Question 13

Give an example of how water causes physical weathering.

Answer 13

1. Ice wedging (this is also an example of how temperature can cause physical weathering)
2. Running water can cause rocks to be round

Question 14

Give an example of how temperature changes can cause physical weathering.

Answer 14

expansion of rocks can cause them to break a part

Question 15

Give an example of how pressure changes can cause physical weathering.

Answer 15

Exfoliation is the process by which the outer layers of rock slowly peel away due to pressure changes.

Question 16

Give an example of how animals can cause physical weathering.

Answer 16

Animals can dig burrow into the ground , allowing more rock to exposed.

Question 17

What do you call it when rock is broken down by the action of other rocks over time? Mechanical action of other rocks.

Answer 17

Abrasion

Question 18

How can wind cause physical weathering?

Answer 18

Wind blown sand can blast small particles away.

Question 19

Give an example of how gravity can cause physical weathering.

Answer 19

Rocks can be broken down in a landslide.

Question 20

How do physical and chemical weathering differ?

Answer 20

Chemical weathering changes both the appearance and the composition of the rock, physical weathering is just the breakdown of the rock into smaller pieces, the composition of the rock does not change.

Question 21

What are the agents of chemical weathering?

Answer 21

oxygen and acids

Question 22

What is one sign that a chemical change has occurred on a rock?

Answer 22

change in color of rock

Question 23

Why do a lot of rocks in southeastern US turn red?

Answer 23

Iron in rocks and soil combines w/ oxygen that dissolves in water. The result is rust.

Question 24

How does acid precipitation cause rocks to weather faster?

Answer 24

When chemicals in the air combine with water they form acids which is stronger than rain water and can form more chemical reactions to break down the rock.

Question 25

Give an example of how groundwater can cause chemical weathering?

Answer 25

underground caves are formed when acidic groundwater flows through cracks and cause further breakdown of the cracks.

Question 26

Give an example of how living organisms can contribute to chemical weathering.

Answer 26

lichens and mosses often grow on rocks and trees. As they grow they produce weak acids that can weather the rock’s surface. This can lead to cracks and breaking a part of the rocks.