# Does freezing a substance change it?

Oct 24, 2017

Freezing is a physical change. It involves a liquid changing states to a solid.

Thus, freezing a substance will not change its chemical identity, but its state.

Nov 5, 2017

For example, when liquid water reaches about ${4}^{0} C$, the liquid achieves its maximum density, at which point the water starts to form ice crystals. Then the change in density of the altered liquid reverses and starts to expand until the ice reaches a lower density at ${0}^{0} C$. As a result, ice floats, which is hugely important to life on earth.
As the temperature of a substance is further reduced, scientists have observed many strange and interesting physical changes taking place, particularly when the temperature is reduced to near absolute zero or ${0}^{0} K$ or $- {273}^{0} C$.