Final answer:
The blue/green stain on sinks, bathtubs, and plumbing fixtures indicates the presence of copper. It can react with water and oxygen to form copper (II) hydroxide, which appears as a blue/green color. To prevent or remove the staining, it may be necessary to install a water treatment system or use cleaning products specifically designed to remove copper stains.
Step-by-step explanation:
The blue/green stain on sinks, bathtubs, and plumbing fixtures indicates the presence of copper. Copper can react with water and oxygen to form copper (II) hydroxide, which appears as a blue/green color. This stain is commonly seen in areas with high copper levels in the water supply.
For example, if the plumbing pipes or fixtures are made of copper, there is a greater chance of copper ions leaching into the water, leading to the blue/green staining.
To prevent or remove the staining, it may be necessary to install a water treatment system or use cleaning products specifically designed to remove copper stains.