Question

Question 4
Liquids generally have lower density as compared to solids. But you must have observed that ice floats on water. Find out why.

Answer 1

The mass per unit volume of a substance is called density (density = mass/volume). As the volume of a substance increases, its density decreases.
Liquids have lower density than that of solids. Water is also a liquid so it should also have less density than that of solid that is ice.
Though ice is a solid, but it has a cage like structure hence there are large number of empty spaces between its particles. These spaces are larger as compared to the spaces present between the particles of water. Thus for a given mass of water, volume of ice is greater than that of water. Hence, the density of ice is less than that of water. A substance with lower density than water can float on water. Therefore, ice floats on water.