Weathering: physical, chemical, and biological

In hydration, some minerals absorb water and increase in volume. In exams, link expansion-induced breakage with hydration.

Burrows allow water and air to enter, increasing chemical and biological action. In exams, consider earthworms and organisms as weathering aids.

Rock composition and structure determine resistance to weathering. In exams, consider rock properties along with climate.

Smaller particles have greater surface area, so reactions can occur faster. In exams, link finer fragments with faster weathering.

Weathering weakens rock and can make slope material ready to move. In exams, link slope instability with weathering.

Carbon dioxide dissolves in water to form carbonic acid, which acts on carbonate rocks. In exams, connect carbonation with acidic water.

Freezing of water is necessary for frost weathering. In exams, look for freeze-thaw cycles, not just cold conditions.

Acidic water can react more rapidly with minerals. In exams, connect acidity with intensity of chemical weathering.

Salts from seawater can accumulate in cracks and create crystal pressure. In exams, remember salt weathering in both coastal and dry settings.

Oxidation, carbonation, and hydrolysis alter mineral chemistry. In exams, distinguish chemical and physical groups clearly.

Soil cover changes the availability of water, air, and organic matter. In exams, connect microenvironment with weathering rate.

Regolith is loose weathered material and bedrock is the solid rock beneath it. In exams, remember their position in a soil profile.

Warmth, moisture, cracks, and time together allow weathering to penetrate deeply. In exams, look for a combination of controlling factors.

Organic acids can chemically weaken minerals. In exams, understand biological weathering in both mechanical and chemical forms.

Repeated expansion and contraction are important for thermal weathering. In exams, connect it with daily temperature range.

Permeability allows water to enter, increasing the zone of chemical reaction. In exams, link permeability with deeper weathering.

Longer exposure allows climate and biological processes to act more. In exams, read time together with climate and rock properties.

Small limestone pieces have greater surface area and more contact with water. In exams, consider both surface area and solubility.

Weathering turns rock into smaller particles and residues. In exams, link weathering products with soil and erosion material.

Biological weathering includes root pressure, burrowing, and organic acids. In exams, understand it as a mixed process.

Soluble minerals dissolve more easily in water and increase chemical weathering. In exams, connect solubility with solution.

Continuous removal exposes new surfaces, but thick regolith cannot persist easily. In exams, understand the balance between weathering and erosion.

Oxidation of iron creates reddish-brown color and rust-like material. In exams, treat color change as a sign of oxidation.

Water expands on freezing and can mechanically break rock. In exams, treat breakage without chemical change as physical weathering.

Weathering is controlled by several factors together. In exams, examine climate, minerals, and cracks together in any example.