9. What is the difference between physical weathering and chemical weathering?

Physical Weathering physically breaks the rock, while Chemical Weathering chemically changes the rock causing it to break.

Explanation: Physical Weathering happens naturally causing the rock to break. An example is roots growing into the concrete causing it to crack. Chemical Weathering on the other hand chemically changes the rock by a chemical reaction. An example is acid rain. Gas or other pollution mixing in with water causing acid rain.

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c. electrical charges of ionic bonds.