Soil Layers and Geochemical Reactions

Vocabulary flashcards covering key concepts from the geology and chemistry lecture notes.

O Horizon

The organic layer of soil, the one closest to the top.

A Horizon

The mineral layer of soil.

E Horizon

Layer of soil made from clay, a zone of leaching.

C Horizon

Parent material in the soil.

B Horizon

Accumulation of clay transported from above.

Al2Si2O5 (Clay)

A common mineral in soil consisting of aluminum, silicon, and oxygen.

Cl2O

Water disinfectant used to purify water.

CaCl2

A simple salt that contains water and is similar to chlorine, sulfate, and carbonate.

Evaporite Reaction

A chemical process that involves the reaction of minerals to yield salts.

Flux

Substance added to reduce melting point and separate other metals.

Primary Mineral

Naturally occurring minerals with a fixed chemical formula, such as KAl2Si2O8.

Secondary Mineral

A mineral that has oxygen, water, and is a clay (silicon/aluminum oxide/hydroxide).

Volcanic Sublimate

A mineral without oxygen that contains elemental sulfur.

Dissolution Reaction

Minerals dissolve directly into water, leaving behind ions.

Hydrolysis Reaction

Water reacts with minerals, particularly silicate minerals, to form new minerals like clay.

Hydration Reaction

Minerals absorb water, causing expansion and reduced resistance to weathering.

Crust Composition

Primarily made of silicon, aluminum, and oxygen.

Acid Hydrolysis

A reaction using a strong acid to catalyze the breaking of molecular bonds by adding water.

Leaching

A hydrometallurgical process that uses chemical solutions to dissolve and extract valuable metals from ore.

Concentration Factor Equation

Percentage mass of metal in ore divided by the average crustal mass percentage.

Alpha decay

A helium nucleus, subtracts 4 from the mass number (top) and 2 from the atomic number (bottom)

Beta decay

mass number stays the same, atomic number increases by one

Positron decay

mass number stays the same, atomic number decreases by one

Electron capture

Mass number stays the same, atomic number decreases by one.