Question

Liquids generally have lower density as compared to solids. But ice floats on water. Explain why?

Answer 1

Density:

• The density of a substance can be defined as the measure of its mass per unit volume which is just the weight for a chosen amount or volume of the material.

Liquids have a lower density than solids:

• liquids are much denser than gases because the molecules of liquids are packed relatively closer to each other than in the gases.
• Also due to the same reason, the density of solids is more than the density of the liquids because the molecules of solid are more tightly packed.

Explanation of ice floating on water:

• It is known that the material or the substance with a lower density tends to float upon the substance with a higher density.
• But, in water, the solid form of water, that is ice having higher density, floats on its liquid form having lower density, that is water itself.
• This is because when water freezes to form ice, voids are created during this process.
• Therefore, although being a solid, ice has a large amount of space between its molecules, which is larger in comparison with the spaces in water molecules.
• Thus, due to this reason, the volume of the ice is more than that of water which explains why water has more density than ice, and therefore, ice floats on water.

Hence, the fact stating, that "liquids generally have lower density as compared to solids, but ice floats on water," has been explained.