Final answer:
Approximately 50% of the total solids in wastewater are considered dissolved solids, requiring subsequent stages of treatment to address these contaminants before safe discharge or reuse.
Step-by-step explanation:
Approximately 50% of the total solids in wastewater are characterized as dissolved solids. Primary treatment of wastewater focuses on solid removal, and even after this stage, dissolved solids remain within the water. Secondary treatment involves bacterial decomposition, where dissolved organic matter is broken down, but this does not completely remove all dissolved solids.
The measurement of total dissolved solids (TDS) is an important parameter in water treatment processes. These consist of various salts, minerals, and organic material that is completely dissolved in the water. Chemistry in everyday life illustrates the significance of dealing with these TDS through various stages of treatment to ensure that water can be released safely back into the environment or reused.