Weathering

Bobby observed that a metal trash can was covered with rust.  What type of weathering caused the rust on the trash can?

• Mechanical weathering 
• Wind weathering
• Chemical weathering
• Erosion weathering

Which type of climate would cause the greatest rate of weathering?

• Cold and dry
• Cold and humid (wet)
• Warm and humid (wet)
• Warm and dry

A student hiking in a rock area on a mountain notices that wide, deep cracks have formed in some of the large rocks. Some of the cracks are so large that the rocks have broken apart. Which process most likely caused these rocks to crack and creak? 

• Erosion by wind
• Water freezing and thawing
• Erosion by fast-moving
• Sediments being deposited.

The surfaces of old concrete statues are often covered with small holes or pits. Which of these MOST LIKELY causes these holes or pits?

• The concrete becomes pitted as water freezes in small cracks in the statue.
• The concrete is chipped away by sand particles blown by strong winds
• The concrete is chemically weathered by acid rain.
• Long exposure to sunlight causes the pits to form.

What is the weathering process in which rocks are broken down into smaller pieces (sediments) and do not change the rock composition?

• Acid weathering 
• Gravity weathering
• Chemical weathering
• Mechanical weathering

Which of the following is the most important agent of chemical weathering to form this cave?

• Water - It can carry acid and dissolve rock
• Erosion - Moves the rocks from one place to another
• Wind - It displaces rocks
• Exfoliation - New cracks give chemical reactions the chance to operate

Weathering is the process of -

• Moving sediment from one place to another

• Dropping or leaving sediment in a location

• Breaking down rocks into sediment

An example of physical weathering is -

• Plant roots and leaves releasing acids

• Carbonic acid dissolving limestone

• Large temperature changes

• Lichens growing on rocks

Over millions of years, weak carbonic acid can dissolve limestone to form -

• Cracks in rocks

• Caves and caverns

• Mountains and cliffs

Fallen plant leaves help break down rocks as they -

• Release or leach acids as they decompose

• Get into cracks, expand, and make the cracks wider

• Scratch and wear away the surface of rocks