What type of substances can be created through the treatment of cyanide with chlorine?

• A. Harmless gases
• B. Highly toxic compounds
• C. Water-soluble salts
• D. Inert compounds

Answer: (B)

The treatment of cyanide with chlorine can lead to the formation of highly toxic compounds, particularly if the reaction is not properly controlled. When chlorine reacts with cyanide, it can produce chlorinated cyanides, which are often more toxic than cyanide itself. These compounds can pose serious environmental and health risks if not managed appropriately.

Understanding the nature of the chemical reactions involved is crucial for wastewater treatment operators. Chlorination has often been employed to manage cyanide levels, but the potential outcomes depend on the concentrations of reactants, the conditions under which the reaction occurs, and other factors present in the wastewater. Therefore, if chlorine is used improperly or excessively in an attempt to neutralize cyanide, it can result in the production of even more hazardous substances, necessitating careful monitoring and control during the treatment process.