Explanation:
This worksheet is about the three main types of weathering: mechanical (physical), chemical, and biological. Each type has a definition and real-world examples. Let’s match each image to the correct type and fill in the blanks.
1.
Top-right image: A rock is shown splitting apart along cracks—like when water freezes in a crack and expands, breaking the rock. This is
mechanical weathering (also called physical weathering).
- Definition: Breaking rocks into smaller pieces *without* changing their composition.
- Examples: Frost wedging (ice expansion), abrasion (sand hitting rock), thermal expansion (heating/cooling).
2.
Middle-right image: A rock with holes and pits, like Swiss cheese — this happens when weak acids (like acid rain) dissolve parts of the rock (e.g., limestone). This is
chemical weathering.
- Definition: Changing the rock’s mineral composition through chemical reactions.
- Examples: Acid rain dissolving limestone, rusting of iron-bearing minerals, oxidation.
3.
Bottom-right image: A tree growing out of a rock, with roots prying it apart. This is
biological weathering (a subset of mechanical, but often taught separately).
- Definition: Weathering caused by living things (plants, animals, microbes).
- Examples: Tree roots cracking rocks, lichens secreting acids, burrowing animals loosening soil/rock.
Now fill in the left-side boxes in order (top to bottom) matching the right-side images:
- Top-left box → matches top-right image →
Mechanical Weathering
- Middle-left box → matches middle-right image →
Chemical Weathering
- Bottom-left box → matches bottom-right image →
Biological Weathering
Let’s write full answers clearly:
Top-left (Mechanical):
Definition: The breaking of rocks into smaller pieces without changing their chemical makeup.
Examples: • Frost wedging • Abrasion by wind or water
Middle-left (Chemical):
Definition: The breakdown of rocks by chemical reactions that change their composition.
Examples: • Acid rain dissolving limestone • Oxidation (rusting) of minerals
Bottom-left (Biological):
Definition: Weathering caused by living organisms.
Examples: • Tree roots growing into cracks and splitting rocks • Lichens producing acids that dissolve rock surfaces
Final Answer:
Mechanical Weathering: Definition — Breaking rocks physically without changing composition; Examples — Frost wedging, abrasion.
Chemical Weathering: Definition — Breaking rocks via chemical reactions that alter composition; Examples — Acid rain on limestone, oxidation.
Biological Weathering: Definition — Weathering by living things; Examples — Roots cracking rocks, lichens secreting acids.
Parent Tip: Review the logic above to help your child master the concept of physical and chemical weathering worksheet.
