Question

is mass density and volume all apart of extensive property

Answer 1

Short answer: Volume and mass are extensive properties; density (mass per unit volume) is an intensive property.

Why:
- Extensive properties depend on the amount of substance and are additive for subsystems (e.g., double the amount → double the mass, double the volume).
- Intensive properties do not depend on the amount of substance (they stay the same when you change the system size), e.g., temperature, pressure, density for a homogeneous substance.

Example: 1 kg of water has mass = 1 kg and volume ≈ 1 L. 2 kg of the same water has mass = 2 kg and volume ≈ 2 L (mass and volume doubled), but density ≈ 1 kg/L in both cases.

Caveats:
- Density can change with temperature, pressure, or composition, so it’s not a universal constant, but it still remains an intensive property for a homogeneous sample.
- For inhomogeneous mixtures, local density varies spatially; then you can treat each region separately.