Weathering and Erosion Weathering is a family of rock breakdown processes that occur at or near the earth's surface Mechanical weathering (also called physical weathering)is when rock physically breaks into smaller pieces Chemical weathering is when chemical reactions, such as oxidation or hydrolysis, dissolve or alter minerals Chemical Weathering Chemical weathering transforms existing minerals into new minerals, and releases ions into the environment For example, the hydrolysis reaction CaAl 2 Si 2 O 8 H 2 CO 3 O2 Al 2 Si 2 O 5 (OH) 4 Ca 2 CO 3 2 turns plagioclase into kaolinite, a clay mineral Kaolinite lacks calcium in its structure, so the leftover calcium from plagioclase enters surface waters as a Ca 2 ion Note that K feldspar and Na Plagioclase can also weather to produce kaolinite clay Think about what ions will be dissolved and enter surface waters when these minerals weather Flag question Question 4 Question 40 25pts The image above shows a freshly broken granodiorite surface on the left, and a chemically weathered granite surface on the right The surface of the chemically weathered granodiorite is coated with the clay mineral kaolinite, formed from hydrolysis of plagioclase (CaAl 2 Si 2 O 8 ) into kaolinite (Al 2 Si 2 O 5 (OH) 4 ) What happened to the calcium that was in the plagioclase Group of answer choices It evaporated and floated off into space It dissolved into surface waters It joined the quartz cystals It radioactively decayed

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Weathering and Erosion Weathering is a family of rock breakdown processes that occur at or near the earth's surface. Mechanical weathering (also called physical weathering)is

Weathering and Erosion

Weathering is a family of rock breakdown processes that occur at or near the earth's surface.Mechanical weathering(also called physical weathering)is when rock physically breaks into smaller pieces.Chemical weatheringis when chemical reactions, such as oxidation or hydrolysis, dissolve or alter minerals.

Chemical Weathering

Chemical weathering transforms existing minerals into new minerals, and releases ions into the environment. For example, the hydrolysis reaction CaAl₂Si₂O₈+ H₂CO₃+ O2 Al₂Si₂O₅(OH)₄+ Ca²⁺+ CO₃^2-turns plagioclase into kaolinite, a clay mineral. Kaolinite lacks calcium in its structure, so the leftover calcium from plagioclase enters surface waters as a Ca²⁺ion. Note that K-feldspar and Na Plagioclase can also weather to produce kaolinite clay. Think about what ions will be dissolved and enter surface waters when these minerals weather.

Flag question: Question 4Question 40.25pts

The image above shows a freshly broken granodiorite surface on the left, and a chemically weathered granite surface on the right. The surface of the chemically weathered granodiorite is coated with the clay mineral kaolinite, formed from hydrolysis of plagioclase (CaAl₂Si₂O₈) into kaolinite (Al₂Si₂O₅(OH)₄).What happened to the calcium that was in the plagioclase?

Group of answer choices

It evaporated and floated off into space.

It dissolved into surface waters.

It joined the quartz cystals.

It radioactively decayed.