Volume change of water during heating.

Density of water: The maximum density of water is/kloc-0 /×10.3 kg/m 3 at 3.98℃, and the density of water is 0.99987×10.3 kg/m 3 at 0℃.

The density of water varies with temperature. In the process of water heating, the mass remains unchanged and the density changes, so the volume changes.

Extended data:

The reason for the density change of water: it is mainly determined by the molecular arrangement. It can also be said that it is caused by hydrogen bonds. Because water molecules have strong polarity, they can combine into associated molecules through hydrogen bonds. Liquid water, except simple water molecules (H? O), but also contains related molecules (H? o)？ And (h? o)？ Wait a minute.

When water does not freeze at 0℃, most water molecules are (H? o)？ When the temperature rises to 3.98℃( 10 1.325kPa), most of the water molecules are (h? o)？ In the form of associated molecules, the space occupied by molecules is relatively reduced, and the density of water is the highest at this time.

If the temperature continues to rise above 3.982℃, the law of general substances expanding with heat and contracting with cold will prevail. When the water temperature drops to 0℃, water becomes ice. When water freezes, almost all molecules associate together to form a huge associated molecule.

The arrangement of water molecules in ice is that each oxygen atom has four hydrogen atoms as its neighbors and two hydrogen bonds. This arrangement leads to an open structure, and there are large gaps in the structure of ice, so the density of ice is inversely proportional to the density of water at the same temperature.