Section 1
Mechanical Forces Break Rocks Apart
Ice wedging, pressure release, plant roots, and abrasion physically break down rocks without changing their composition. These forces split rocks into smaller pieces, increasing their surface area.
In this Grade 6 Earth Science lesson from Chapter 4, students learn how mechanical weathering and chemical weathering break down rocks into smaller pieces. The lesson covers specific processes such as exfoliation and abrasion, and examines the factors that affect the rate at which weathering occurs. Students also practice identifying variables through a hands-on experiment exploring rust formation.
Section 1
Mechanical Forces Break Rocks Apart
Ice wedging, pressure release, plant roots, and abrasion physically break down rocks without changing their composition. These forces split rocks into smaller pieces, increasing their surface area.
Section 2
Chemical Reactions Transform Rock Composition
Water and air cause chemical weathering by dissolving minerals or changing them into different compounds. Slightly acidic rainwater breaks down minerals, while oxygen combines with iron to create rust.
Section 3
Environmental Factors Control Weathering Rates
Surface area, rock composition, and climate determine how quickly rocks break down. More exposed surface accelerates weathering, while different rock types weather at varying speeds. Hot, wet climates favor chemical weathering.
Section 4
Weathering Processes Work Together Over Time
Mechanical weathering increases rock surface area, allowing chemical weathering to affect more of the rock. Both processes work together, breaking down rocks over hundreds or thousands of years.
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Section 1
Mechanical Forces Break Rocks Apart
Ice wedging, pressure release, plant roots, and abrasion physically break down rocks without changing their composition. These forces split rocks into smaller pieces, increasing their surface area.
Section 2
Chemical Reactions Transform Rock Composition
Water and air cause chemical weathering by dissolving minerals or changing them into different compounds. Slightly acidic rainwater breaks down minerals, while oxygen combines with iron to create rust.
Section 3
Environmental Factors Control Weathering Rates
Surface area, rock composition, and climate determine how quickly rocks break down. More exposed surface accelerates weathering, while different rock types weather at varying speeds. Hot, wet climates favor chemical weathering.
Section 4
Weathering Processes Work Together Over Time
Mechanical weathering increases rock surface area, allowing chemical weathering to affect more of the rock. Both processes work together, breaking down rocks over hundreds or thousands of years.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter