1. Weathering Compare and contrast mechanical and chemical weathering.
Explain how weathering affects Earth’s surface.

2. Weathering Define weathering
surface processes that break down rock into small pieces called sediment

3. Weathering Focus Question
Explain why over long periods of time, weathering wears mountains down to rolling hills…
Rocks at the tops of mountains are broken down by weathering, and sediment is moved downhill by gravity, water, and ice.

4. Weathering Describe mechanical weathering
Physical processes that break rock into fragments with the same chemical makeup and characteristics as the original rock

5. Weathering Identify what can cause mechanical weathering
growing plants
burrowing
animals
expanding ice

6. Weathering Focus Question
Speculate how damage to a sidewalk, due to growing plants, could be avoided…
Plant trees farther away from the sidewalk. Remove large roots. Build sidewalks farther away from mature trees.

7. Weathering ice wedging. Identify what happens in
water enters cracks in rock
water freezes and expands
expanding ice breaks rocks apart

8. Weathering Explain why size is important to weathering rock.
Surface area-
Small pieces of rock have more surface area than do larger pieces, which makes them weather faster.
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9. Weathering
Explain why size is important to weathering rock.

10. Weathering Describe chemical weathering
Chemical reactions dissolve the minerals in rocks or change them into different minerals.

11. Weathering Explain how carbonic acid weathers rock.
Carbonic acid, formed from water reacting with carbon dioxide, causes calcite in limestone to dissolve (which could form caves).

12. Weathering Explain how kaolinite clay forms.
It forms when natural acids react with feldspar in granite and other rocks. Clay is an end product of weathering.

13. Weathering Explain why groundwater is acidic.
As water seeps through soil, it reacts with carbon dioxide in soil and air to form carbonic acid.

14. Weathering Define oxidation
Chemical process that occurs when iron is exposed to oxygen in the air

15. Weathering Define climate Pattern of weather that occurs over time
Cold climate
Warm, wet climate
Pattern of weather that occurs over time
Mechanical weathering more rapid in cold climates
Chemical weathering more rapid in warm, wet climates

16. Weathering
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17. Weathering
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