The pH of water sample collected from a river was found to be acidic in the range of 3.5 – 4.5, on the banks of the river were several factories that were discharging effluents into the river. The effluents 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
Lead is a significant constituent of lead-acid battery utilized widely in vehicle batteries. The release of lead from battery fabricating processing plants can bring down the pH of river water.
Soap is a combination of a weak acid and a strong base, which results in a salt that is basic on the pH scale. It does not lower the pH of river water.
Similarly, Plastic cup manufacturing factory and Alcohol distillery does not lower the pH of river water
Hence option (b) is correct.