Unit 1 Lesson 2

Question 1

Weathering

Answer 1

The breakdown of rock material by physical and chemical processes
physical weathering
chemical weathering

Question 2

Physical Weathering

Answer 2

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

Question 3

Agents of physical weathering

Answer 3

-Temperature changes
-Pressure changes
-Plant and animal actions
-Water
-Wind
-Gravity

Question 4

Temperature Changes

Answer 4

Rise in temperature causes rock to expand

Decrease in temperature will cause a rock to contract

Repeated temperature changes weakens the rock

Question 5

Ice wedging (Frost Wedging)

Answer 5

Water collects in cracks in the rock. When the temp drops, the water expands and forms ice. The ice causes the cracks to widen. Eventually, the rock will split apart

Question 6

Pressure Changes

Answer 6

Rocks formed deep in the earth become exposed at the surface. As the pressure on the rock decreases, the rock expands

Question 7

Exfoliation

Answer 7

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

Question 8

Abrasion

Answer 8

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

Caused by:
-Moving water
-Wind
-Gravity

Question 9

Chemical Weathering

Answer 9

The breakdown of rocks by chemical reactions

Question 10

Oxidation

Answer 10

The process by which other chemicals combine with oxygen

Example: Rust forms when iron in rocks and soil combine with oxygen

Question 11

Acid precipitation

Answer 11

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

When fossil fuels are burned, chemicals combine with water in the atmosphere to produce acids. When the acids fall to earth this is acid precipitation