To boil water it requires heat , what happens to the heat when the water cools down as energy can neither be destroyed nor be created ?

Explanation:

The water particles just flow through each other. They cannot be destroyed nor created.

The water cooling down is due to evaporation, the heat is simply changing the state of matter of the water. Energy is being used to change it's state. Evaporation causes the cooling down of something. Think of sweat?

Explanation:

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.