What is weathering?

• The temperature of the air.

• The act of sharing the weather forecast.

• The changing of the Earth's surface through chemical or physical processes.

What is physical weathering?

• The breaking down of rocks by physical and chemical processes.

• When weather causes physical changes to the Earth's surface, such as in the example of breaking larger rocks into smaller ones.

• When weather, temperature, pressure, plant and animal actions, and wind, water and gravity cause chages to the Earth's surface.

• When reactions to oxygen, acid precipitation, and acids in groundwater or in living things break down the Earth's surface.

What is chemical weathering?

• When reactions to oxygen or acids cause changes to the Earth's surface.

• When weather causes larger landforms to breakdown into smaller ones, such as when when a larger rock is broken down into a smaller one.

• When the wind, rain and gravity causes changes to the Earth's surface.

This is showing an example of______________________.

• physical weathering

• chemical weathering

• acid precipitation

• erosion

Oxidation is_____________________________.

• an example of chemical weathering

• when oxygen reacts with compounds in rocks, causing a reaction

• when the oxygen in the air mixes with precipitation

What causes acid precipitation?

• When acids in the air combine with water in the air, and the combined chemicals fall as rain or snow.

• When the oxigen in the air combines with the water in the air, and then falls to the ground as rain or snow.

• When the acid in groundwater evaporates into the air, and falls to the ground as rain or snow.

The following are agents of physical weathering:

• acid precipitation and acid in ground water

• oxidation

• animal action and plant action

• wind, water and gravity

• temperature and pressure changes

How do animals cause changes to the Earth's surface?

• They dig in the ground, moving soil and small rocks.

• They move dirt on their feet as they walk around.

• They expose rock when they dig.

• They cause abrasions and erosion on the rocks they dig up.

A rise and fall in temperature over and over causes __________________ in rocks.

• a chemical change

• erosion

• abrasion

• deposition

• a physical change

How do plants cause physical changes to the Earth's surface?

• The roots cause pressure on exposed rock, breaking it apart.

• The weight of the plant, such as a big tree, puts pressure on the rocks.

• The water from the plants has chemicals in them, causing the rock to erode.