Massachusetts Wastewater Practice Exam

True or false: Chlorine is used as a reducing agent in the treatment of cyanide.

1. True.

2. False.

3. It depends on the concentration.

4. Only in certain processes.

The correct answer is: False.

In the context of wastewater treatment, chlorine is primarily known as an oxidizing agent rather than a reducing agent. When treating substances like cyanide, chlorine reacts with cyanide to convert it into less harmful compounds through an oxidation process. This is significant because cyanides can pose serious environmental and health risks, and effective treatment is necessary to neutralize their toxicity. In contrast, reducing agents are substances that donate electrons to other substances in chemical reactions, thereby reducing their oxidation states. Chlorine does not function in this way when dealing with cyanides; its role is to oxidize rather than reduce. Moreover, it's important to note that while other agents could be used as reducing agents in specific chemical contexts, chlorine does not fit into that category for the treatment of cyanide. This solidifies the understanding that the statement regarding chlorine being a reducing agent in this scenario is false.