Interpretation:
The reason for increased concern about using lead in fishing lines and the affect of water temperature on it is to be discussed.
Concept Introduction:
Water gets polluted due to the presence of various biological and chemical contaminants in it. Biological contaminants include microorganisms such as giardia, legionella and chemical contaminants such as mercury, lead, benzene, tri chloroethylene etc. Both these render water unfit for consumption by human beings and animals, if the contaminant exceeds a certain limit, which is termed as the Maximum Contaminant Limit.
The amount of a contaminant is reported as the mass of contaminant (in milligrams) present in one liter of water.
Hard water is a solution of calcium and magnesium salts in water. Presence of calcium and magnesium ions makes the water hard, and renders it unusable for various purposes such as cleaning clothes and utensils, bathing and also makes it unfit for water heaters.
Boiling of water cannot get rid the water of contaminants because it decreases the total volume of the sample while the mass of the contaminant remains the same. Moreover, the concentration of the contaminant increases.
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Chemistry In Focus
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