Back
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

chemical weathering

Primary Information
Secondary Information

Definition

Chemical weathering is the breakdown of rocks and minerals through the action of chemical reactions.

The most common chemical weathering agents are water, oxygen, and carbon dioxide. These chemicals can react with the minerals in rocks to form new substances, which can then be washed away by water.

Chemical weathering is an important process in the formation of soil and the development of landscapes.

Here are some examples of chemical weathering:

  • Hydrolysis: This is the process of a mineral reacting with water to form a new substance. For example, the mineral feldspar can react with water to form clay.
  • Oxidation: This is the process of a mineral reacting with oxygen to form a new substance. For example, the mineral iron can react with oxygen to form rust.
  • Carbonation: This is the process of a mineral reacting with carbon dioxide to form a new substance. For example, the mineral limestone can react with carbon dioxide to form calcium carbonate.

How can the word be used?

A naturally occurring, inorganic solid that has a definite chemical composition and a characteristic crystal structure.

chemical weathering

Different forms of the word

Noun:

Singular: chemical weathering.

Plural: chemical weatherings.

Adjective:

Chemical weathering: relating to the breakdown of rocks and minerals by chemical reactions.

Verb:

Chemically weather: to break down rocks and minerals by chemical reactions.

Etymology

The word "chemical weathering" comes from the words "chemical" and "weathering". The word "chemical" comes from the Greek word "khēmikós", which means "of or relating to alchemy". Alchemy was a medieval practice that attempted to transform base metals into gold. The word "weathering" comes from the Old English word "weðrian", which means "to become exposed to the weather".

Question

What is the evidence of chemical weathering?

AQA Science Exam Question and Answer

Question:

Define "chemical weathering" and provide an example of a natural process that involves chemical weathering.

Answer:

"Chemical weathering" refers to the breakdown and alteration of rocks and minerals through chemical reactions.

Example of Natural Process Involving Chemical Weathering:

An example of a natural process that involves chemical weathering is the formation of caves and sinkholes in limestone regions. Limestone is primarily composed of calcium carbonate (CaCO3). Over time, rainwater, which is slightly acidic due to dissolved carbon dioxide, seeps into the limestone rock. The acidic water reacts with the calcium carbonate, leading to the dissolution of limestone and the creation of underground cavities and passages. This process is called "carbonation" and is a typical example of chemical weathering affecting the Earth's surface.