What is identified as an agent of chemical weathering?

The identified agent of chemical weathering in this context is oxygen. In the process of chemical weathering, oxygen plays a crucial role in the oxidation of minerals. This process alters the chemical composition of rocks, leading to changes in their structure and the subsequent breakdown of those rocks. For example, when oxygen interacts with iron in minerals, it can lead to the formation of iron oxides, which contribute to the rusting process and the overall degradation of the rock.

While water, carbon dioxide, and nitrogen have their own roles in geological and environmental processes, they are not the primary agents of chemical weathering in the same way that oxygen is. Water is essential for facilitating chemical reactions but is generally classified as a solvent rather than a direct agent of chemical change. Carbon dioxide can also contribute to weathering, particularly in the formation of weak carbonic acid when dissolved in water, but it is not as commonly singled out as oxygen in the context of chemical weathering. Nitrogen does not have a significant role in this process.