Final answer:
Most ion exchange surfaces in soil are negatively charged, which could attract positively charged molecules like crystal violet, but the soil system as a whole remains electrically neutral. The soil's charge related to crystal violet depends on its composition and the ion exchange surfaces present.
Step-by-step explanation:
The question revolves around whether soil is negatively charged when crystal violet passes through it. According to chapter 370 of a reference material discussing 'SOILS,' most ion exchange surfaces in soil are negatively charged and are therefore cation exchange surfaces. This characteristic would suggest that the charge of soil could interact with compounds like crystal violet, which is a cationic dye. However, it is important to note that the soil retains an overall neutral charge because positive and negative charges balance each other out.
Therefore, while ion exchange surfaces in the soil may be negatively charged, which could attract positively charged molecules such as crystal violet, the complete soil system remains electrically neutral. The question focuses on the soil's ability to interact with ions through ion exchange surfaces and does not directly relate to the water potential of plants or soil, which deals with the tendency of water to move from one area to another.
To fully understand the soil's interaction with crystal violet or other charged molecules, one must consider the soil composition, which includes the abundance and nature of ion exchange surfaces, and how these interact with the molecules passing through the soil.