Question

The pH of a water sample found in the river was found to be acidic in the range of 3.5-4.5, on the banks of the river there were several factories that were discharging effluents into the river. The effluent of which one of the following factories is the most likely cause for lowering the pH of river water?
A. Soap and detergent factory
B. Lead battery manufacturing factory
C. Plastic cup manufacturing factory
D. Alcohol distillery

Answer 1

Hint:- Wastewater from manufacturing or chemical processes in industries contributes to water pollution. Industrial wastewater usually contains specific and readily identifiable chemical compounds. Water pollution is concentrated within a few subsectors, mainly in the form of toxic wastes and organic pollutants. These organic pollutants as well as toxic substances have different pH depending upon the source of wastewater.

Complete step-by-step solution:-
Industrialization plays a vital role in growth and development of any country and it started earlier in the UK than USA and thereafter industries are established in advance as well as under developed and developing countries throughout the globe. In India, industrial establishment was done around 50 decades ago, in majority after the independence, large and small cottage industries began operation.
Effluent is defined as any outflowing water or gas to a natural body of water, from a structure such as a wastewater treatment plant, sewer pipe or industrial outfall. It generally refers to a stream exiting a chemical reactor.
Effluents from different factories have different pH ranges, such as effluents from soap or detergent industries have slightly alkaline pH, due to presence of sodium sulphate ions or some other ions responsible for increasing pH of the water. Similarly effluents from alcohol distillery and plastic cup manufacturing factories have slightly alkaline pH range. Whereas, lead manufacturing factories use acids in lead batteries which have lower pH and when discharged into nearby water bodies are more likely to lower pH value of the water.
So, the correct answer is option B.

Note:- effluents from lead battery manufacturing factories are composed of some materials of high polluting potential, especially Pb, Cd and other highly toxic heavy metals, as well as the risk posed by their high sulphuric acid concentration.