Weathering: Mechanical and Chemical

What is the difference between mechanical and chemical weathering?

• Mechanical weathering has no effect on rocks

• Mechanical weathering breaks down rocks through chemical reactions

• Chemical weathering breaks down rocks physically

• Mechanical weathering breaks down rocks physically, while chemical weathering breaks down rocks through chemical reactions.

Give an example of mechanical weathering.

• Frost wedging

• Chemical reaction

• Volcanic eruption

• Tectonic plate movement

Give an example of chemical weathering.

• Erosion of rocks

• Freezing of water

• Rusting of iron

• Formation of mountains

How does frost action contribute to mechanical weathering?

• Frost action has no impact on mechanical weathering

• Frost action causes rocks to become harder and more resistant to weathering

• Frost action leads to the formation of new minerals in rocks

• Frost action causes the expansion of water in cracks, leading to the mechanical breakdown of rocks.

What role does water play in chemical weathering?

• Water inhibits chemical reactions in weathering

• Water has no role in chemical weathering

• Water acts as a solvent and a medium for chemical reactions.

• Water causes mechanical weathering, not chemical weathering

Explain how plant roots contribute to mechanical weathering.

• Plant roots release chemicals that dissolve the rocks

• Plant roots absorb water from the rocks, causing them to dry out and crumble

• Plant roots have no impact on mechanical weathering

• Plant roots grow into cracks in rocks and exert pressure as they expand, causing the rocks to break apart.

What is the main agent of chemical weathering?

• Wind and sand

• Sunlight and heat

• Plants and animals

• Water, oxygen, carbon dioxide, and acids

How does temperature change contribute to mechanical weathering?

• Temperature change has no effect on mechanical weathering

• Temperature change causes rocks to harden and become more resistant to weathering

• Temperature change causes rocks to expand and contract, leading to stress and eventual breakage.

• Temperature change causes rocks to melt and disintegrate

What are the effects of mechanical weathering on rocks?

• It increases the size of rocks without changing their composition

• It turns rocks into a different type of mineral

• It breaks down rocks into smaller pieces without changing their chemical composition.

• It causes rocks to melt into liquid form

What are the effects of chemical weathering on rocks?

• Increase in hardness

• Decrease in weight

• Changes in composition and structure

• No change in appearance