GEOG REVISION 8

Weathering is

• Breaking of rocks due to natural disasters

• Breaking and carrying away of the broken materials

• Breaking of rocks because of temperature, water, chemicals and life forms.

• Breaking of rocks due to Wind and Hurricane.

Acid rain causes

• physical weathering.
• chemical weathering.
• both chemical and physical weathering.
• neither chemical or physical weathering.

Freezing causes

• physical weathering.
• chemical weathering.
• both chemical and physical weathering.
• neither chemical or physical weathering.

Tree roots cause

• biological weathering

• chemical weathering.

• both chemical and physical weathering.

• neither chemical or physical weathering.

Physical and chemical weathering both

• change rocks into new materials.
• dissolve rocks.
• break rocks into smaller pieces.
• require exposure to air.

Physical and chemical weathering differ because

• only chemical weathering produces new materials.
• only physical weathering creates smaller pieces of rock.
• only physical weathering involves water.
• chemical weathering is faster than physical weathering.

An example of chemical weathering is -

• Ice wedging

• Oxidation

• Animals burrowing

• Crashing waves

Carbonic acid is formed in nature when -

• Water dissolves particles of soil to form mud

• The oxygen molecules in water bond with minerals in rocks

• Water bonds with carbon dioxide in the air and/or soil

Feldspar turning into the clay is an example of

• Oxidation

• Saltation

• Hydrolysis

• Carbonation

Biological weathering is caused when

• Any life form causes weathering

• Only roots of the trees cause weathering

• Burrowing animals cause weathering