RAP 1/22 pg. 4 What is weathering? As shown below, an empty 1,000.-milliliter container has a mass of 250.0 grams. When filled with a liquid, the container and the liquid have a combined mass of 1,300. grams. What is the density?

RAP 1/23 pg 4 The picture below is an example of what type of weathering? 2. Explain why you think this.

Topic: Weathering, Soil and Erosion Chapter 12 in book Section: 12.1 - Weathering Section: 12.2 - Soil Section: 12.3 - Mass Movements & Erosion Section: 12.4 - Soil as a Resource

Weathering: breakup of rock due to exposure to processes that occur on Earth’s surface

Two types: Chemical Mechanical -minerals are changed into different substances Mechanical -split or broken into smaller pieces *no change in composition

1. Abrasion Breakdown of rock by grinding action Mechanical

Water freezes in the cracks of rocks and expands Mechanical 2. Frost Wedging Water freezes in the cracks of rocks and expands Mechanical

Root Pry

Lichen - a symbiosis between algae and fungus. Secretes acid Lichen - a symbiosis between algae and fungus. Secretes acid. It is the most important producer of soil from rock.

Roots pry open crackx Mechanical Chemical Lichen secrete acid 3. Plant and Animal Activity Roots pry open crackx Mechanical Chemical Lichen secrete acid

Peeling of surface layers Mechanical 4. Exfoliation Peeling of surface layers Mechanical

Reaction of water with other substances Chemical 5. Hydrolysis Reaction of water with other substances Chemical

Dissolves minerals like calcite and rocks like limestone Chemical 6. Acids Dissolves minerals like calcite and rocks like limestone Chemical

1908 1968

Reaction of oxygen with other substances 7. Oxidation Reaction of oxygen with other substances Example: rust Chemical

Types of Chemical Weathering ?????????? oxidation ?????????? acid rain ?????????? hydrolysis

RAP 1/29 pg 4 Which rock was most likely found in the bottom of a riverbed? 2. What type of weathering is responsible for the river rock?

Alka Seltzer Lab Follow along with teacher demonstrations. Answer Alka Seltzer Analysis Questions on pg. 6 (Due 1/30)

RAP 1/30 pg. 8 In the alka seltzer lab, what two things changed the weathering rates? Which substance plays the most important role in chemical weathering?

Weathering Quiz (1/30)

Rates of Weathering Surface Area Climate Composition a. More surface exposure = faster a. Wet = faster; Dryer = slower a. Faster = shale; Slower = quartz

Where do leaves decay faster?

=differential weathering Erosion has stripped away the overlying rock and Seneca Rocks have been uplifted quartzite =differential weathering