Question

Water should not be left open and stagnant in a place because microbes could grow on it.
If it is not possible to remove water from the place, oil could be poured over it. Can you
think of a reason for this?

Answer 1

Answer:

If water is left open and stagnant in a place microorganisms grow. To avoid the growth of microorganism, oil is poured into the water and because of the light nature of oil, it forms a layer over water which restricts the microorganism to develop in it and hence growth of microorganisms are blocked.