Physical properties can help to identify a substance. Density can be used to identify and classify different types of matter. 

As stated previously, melting point, as well as boiling point, can be used to describe matter. Consider water and its different states of matter. Water freezes or melts at 0 degrees Celsius. It boils at 100 degrees Celsius. Its density is 1 gram/cubic centimeter. It is clear, polar, and odorless. Water is still water whether it is solid, liquid, or gaseous.