Question

43. Paheli was feeling thirsty but there was only a pot of water at home which was muddy and unfit for drinking. How do you think Paheli would have made this water fit for drinking if the following materials were available to her?

Alum, tub, muslin cloth, gas stove, thread, pan and lid.

Answer 1

Here two processes are involved Filtration, Decantation

Filtration: The process of removing insoluble solid from a liquid by using the filter.

Decantation: The process of transfer of clean liquid from one vessel to another vessel without disturbing the sedimented particles

To cleanse water, Paheli could perform the following measures.

• To begin, use a muslin cloth to filter the muddy water.
• Now, bind the alum piece with thread and soak it in water for a while, then leave the water alone.
• The contaminants will settle at the bottom after some time, and the water from the top can be decanted.
• In a covered pan with a lid, bring the decanted water to a boil for about 10 minutes. Filter the water once it has cooled down.
• The filtered water is safe to consume.