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Chemical versus physical weathering; factors

Short answer

Physical weathering mechanically breaks rocks without mineral change (frost wedging, exfoliation), while chemical weathering alters minerals via solution, hydrolysis and oxidation. Factors are climate, rock type and structure, topography, vegetation and time.

Differentiate between chemical and physical weathering. What are the factors of weathering of rocks?

PointPhysical weatheringChemical weathering
ChangeRock breaks into pieces; minerals unchangedMinerals change to new minerals
Main agentsTemperature, frost, pressure release, rootsWater, CO2_2, oxygen, acids
Favoured byCold or dry climates, steep slopesWarm, humid climates
ProcessesFrost wedging, exfoliation, thermal stressSolution, hydrolysis, oxidation, carbonation
ProductsAngular fragments, sandClay, oxides, soluble salts
Link between themIncreases the surface area, which speeds up chemical weatheringWeakens the rock, which helps it break up physically

Factors of weathering

  1. Climate: temperature and rainfall. Frost action dominates in cold areas; chemical weathering in hot, humid areas.
  2. Rock type and mineral composition: quartz is very resistant; olivine, feldspar and calcite weather quickly.
  3. Rock structure: joints, bedding and faults let water and air enter.
  4. Topography (relief): steep slopes remove debris and expose fresh rock; gentle slopes keep a thick soil cover.
  5. Vegetation and organisms: roots, bacteria and humic acids speed up weathering, but dense cover also protects the surface.
  6. Time: the longer the exposure, the deeper the weathering.
  7. Grain size and porosity: coarse or porous rocks have more surface for reaction.

✓ Answer checked by Claude Opus 5.5 (high effort)

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