Weathering

Carbon dioxide (CO2) combines with water as raindrops fall through the atmosphere. This makes a weak acid, called carbonic acid. Carbonic acid is a very common in nature, where it works to dissolve rock. Pollutants, such as sulfur and nitrogen from fossil fuel burning, create sulfuric and nitric acid. Sulfuric and nitric acids are the two main components of acid rain, which speeds up chemical weathering.
This statue was probably destroyed by _____.

• Wind
• Humans
• Acid Rain
• Animals

Chemical weathering is the other important type of weathering. Chemical weathering may change the size of pieces of rock materials, but definitely changes the composition. So one type of mineral changes into a different mineral. Chemical weathering works through chemical reactions that cause changes in the minerals.
True or false: chemical weathering causes rocks to change into new types of rocks.

• True
• False

Which of the following probably did not cause this statue to wear down?

• Rain
• Wind
• Snow
• Animals

Oxidation is a chemical reaction that takes place when oxygen reacts with another element. Oxygen is very strongly chemically reactive. The most familiar type of oxidation is when iron reacts with oxygen to create rust.
Which chemical creates rust?

• Oxygen
• Carbon Dioxide
• Nitrogen
• Neon

The statue of liberty is made of copper. It was originally brown but has since turned green. This is probably due to _______.

• Oxygen
• Acid Rain
• Carbon Dioxide
• Humans

How does freezing water cause the weathering of rocks?  The freezing water—

• keeps the rocks in place
• makes the rocks last longer
• expands cracks and breaks rocks
• causes rocks to fall in landslides

The process that breaks down rocks and other materials on Earth's surface is called

• weathering
• erosion
• soil conservation
• decomposition

How does wind abrasion work?

• Sediment is blown off a surface from wind.
• Wind-blown sediment strikes a surface.
• Wind blows large chunks of rock off a surface.
• Sediment falls off of a surface on its own.

During chemical weathering, what can happen to the type of rock that has undergone chemical weathering?

• a new rock is produced that is larger than the original rock
• a new rock is produced that is the same as the original rock
• a new rock is produced that is different from the original rock 
• no new rock is created - it is just smaller in size

What is mechanical weathering?

• Process through which rocks are physically broken into smaller pieces.
• Rocks are broken down through chemical changes.
• Rocks are worn away from acid in plant roots.
• Rocks broken down by machinery.