Weathering Review

The natural chemical or physical processes that breaks down rock on Earth's surface.

• weathering

• erosion

• deposition

• jackhammering

Answer explanation

Weathering is the natural process that breaks down rocks on Earth's surface through chemical or physical means. Erosion involves the movement of these broken materials, while deposition refers to their accumulation elsewhere.

Tags

NGSS.MS-ESS2-2

This type of weathering occurs when rocks weaken then break down due to chemical changes in the composition of the rock.

• mechanical weathering

• chemical weathering

• erosion weathering

• deposition

Answer explanation

Chemical weathering involves the breakdown of rocks through chemical changes in their composition, leading to weakening and disintegration. This distinguishes it from mechanical weathering, which does not alter the rock's chemical structure.

Match the following processes with their examples:

• Water freezes in cracks of rocks, causing them to break apart.

• acid rain

• Rainwater mixed with pollutants causes rock surfaces to dissolve.

• chemical weathering

• Rocks change composition due to chemical reactions.

• ice wedging

• Rocks are made smooth by wind blowing smaller particles across their surface.

• abrasion

Answer explanation

The rocks were smoothed by wind-driven particles, illustrating abrasion, which is the process of wearing down surfaces through friction. This distinguishes it from other weathering types like ice wedging or chemical weathering.

Tags

NGSS.MS-ESS2-2

These rocks were broken apart from the continuous freeze/thaw of water in the cracks of the rocks. This is an example of:

• ice wedging

• acid rain

• permeability

• abrasion

Answer explanation

The process described is ice wedging, where water seeps into cracks, freezes, and expands, causing the rocks to break apart. This repeated freeze/thaw cycle is a key example of mechanical weathering.

Tags

NGSS.MS-ESS2-1

NGSS.MS-ESS2-2

How might a weathered mountain appear different than an unweathered mountain?

• Weathered mountain would be taller.

• Weathered mountain would be rounder and less jagged.

• Weathered mountain would be more jagged and less rounded.

• Weathered mountain would have no trees.

Answer explanation

A weathered mountain appears rounder and less jagged due to erosion, which smooths its features over time. In contrast, an unweathered mountain retains sharper, more rugged edges.

Tags

NGSS.MS-ESS2-2

Weeds growing into the cracks in a sidewalk and the sidewalk begins to crumble is an example of:

• mechanical weathering

• chemical weathering

Answer explanation

Weeds growing in sidewalk cracks exert pressure as they grow, causing the sidewalk to crumble. This process is an example of mechanical weathering, where physical forces break down materials without changing their chemical composition.

Tags

NGSS.MS-ESS2-2

Weathering is the breaking down of rock into ___________.

• boulders

• sediment

• ice

• mountains

Answer explanation

Weathering is the process that breaks down rocks into smaller particles. These smaller particles are known as sediment, making it the correct answer. Other options like boulders, ice, and mountains do not accurately describe the result of weathering.

Tags

NGSS.MS-ESS2-2

Which of the following is NOT an agent of chemical weathering?

• carbon dioxide

• acid rain

• ice wedging

• oxidation

Answer explanation

Ice wedging is a physical weathering process caused by the expansion of freezing water, not a chemical one. In contrast, carbon dioxide, acid rain, and oxidation involve chemical reactions that alter minerals.

How do plants weather rocks?

• during photosynthesis

• when roots grow into cracks of rocks and expand the rock

• when the plant moves water from the roots to the leaves

Answer explanation

Plants weather rocks primarily when their roots grow into cracks in the rocks. As the roots expand, they exert pressure that can break the rock apart, facilitating weathering.

What type of weathering is occurring in the picture?

• Mechanical

• Biological

• Chemical

Answer explanation

Chemical weathering occurs when minerals in rocks undergo chemical reactions, often involving water and acids, leading to changes in their composition. This is the type of weathering depicted in the picture.

Tags

NGSS.MS-ESS2-2