Density is an example of an intensive physical property of matter? what does this statement mean?

Question

chemistry 1151

Answer 1

In physics and chemistry particularly in thermodynamics and physical chemistry you differentiate between extensive and intensive physical properties.
An intensive property of a system is a physical property of the system that does not depend on the system size or the amount of material in the system. By contrast, an extensive property of a system does depend on the system size or the amount of material in the system.
Therefore if you add two systems the extensive properties in contrast to the intensive properties add up. Consider two glasses of water at different temperature, which are mixed. The total energy of the mixture (extensive) equals the sum of the energy before mixing. The temperatures (intensive) does not add up.
If you apply this concept on physical properties of mater, you can see that most physical properties of matter, like density, viscosity, specific enthalpy etc. are intensive. If you mix two materials with different density, the density of the mixture is not the sum of the original densities. The density of the mixture is usually at a level between the original densities.

Answer 2

This statement means that density is independent of amount of matter present

ex density of water liquid is 1g/cm^3

If you have 1 milliliter or 1 liter that statement remains true
So density is intensive

Ex for the contrary mass of water
1 cm^3 of water =1g
1 liter of water = 1kg

So mass is extensive depend on the amount of water