Ice floats on water. This happens so because ice has lesser density than water. Scientists have proven that water has a density of 1.0gm/cubic cm while on the other hand, ice has density of 0.931gm/cubic cm.
The process where water converts into ice, gives the hydrogen bonding a scope to expand and get placed further apart. As a result, forcing it to take more space, decreasing the overall density and hence, making to float in the water.
Generally, pure water gets converted into its solid state at 0 degree Celsius, this is also known as its freezing point. In other words, the constant temperature at which water changes into ice is called as solidification or freezing point.
To convert water to ice it releases about 80 calories (or 4200 J/Kg) of heat energy and is this is known as specific latent heat of fusion of Ice. It is the amount of heat required to change ice at 0 degree into water at 0 degree centigrade without change in its temperature, here the amount of heat absorbed by ice is used in increasing the potential energy of its molecules.
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