Which component is NOT typically associated with soil?

Carbon dioxide is indeed a gas that can be found in soil, particularly in the spaces between soil particles, but it is not a solid or liquid phase component that typically defines soil makeup. The primary components of soil include mineral matter, organic matter, and air, which together form the physical structure and characteristic qualities of soil.

Mineral matter provides essential nutrients and forms the backbone of soil structure. Organic matter, which includes decomposed plant and animal material, enriches the soil with nutrients and improves its structure and moisture retention capabilities. Air in the soil is crucial for the respiration of roots and soil organisms, contributing to the overall health of the soil ecosystem.

In contrast, while carbon dioxide does play an important role in biological processes within the soil, it is not considered a fixed component of soil itself, which highlights why it is not typically associated as a primary component. This distinction emphasizes the solid and liquid phases of soil that underpin its function and formation.