Which statement correctly describes the pH of acidic wastewater?

Which statement correctly describes the pH of acidic wastewater?

• A. PH values above 7 indicate acidity
• B. pH of 7 indicates acidity
• C. pH less than 7 indicates acidity
• D. pH of 12 indicates acidity

Answer: (C)

Understanding pH and acidity is the key idea. The pH scale runs from 0 to 14, where lower values are more acidic, 7 is neutral, and higher values are more basic (alkaline). Acidic wastewater is defined by having a pH below 7, so the statement that pH less than 7 indicates acidity is the correct one. A pH of 7 is neutral, not acidic; a pH above 7 is basic, and a very high pH like 12 is strongly basic, not acidic. Maintaining appropriate pH helps prevent corrosion, protects treatment processes, and ensures discharge limits are met.

Understanding pH and acidity is the key idea. The pH scale runs from 0 to 14, where lower values are more acidic, 7 is neutral, and higher values are more basic (alkaline). Acidic wastewater is defined by having a pH below 7, so the statement that pH less than 7 indicates acidity is the correct one. A pH of 7 is neutral, not acidic; a pH above 7 is basic, and a very high pH like 12 is strongly basic, not acidic. Maintaining appropriate pH helps prevent corrosion, protects treatment processes, and ensures discharge limits are met.