Bulk density og tapped density

Bulk density is the mass of powder loosely packed (freely settled) into a container divided by the total volume. The total volume includes particle volume, inter-particle void volume and internal pore volume.

Tapped density is the term used to describe the bulk density of a powder (or granular solid) after consolidation/compression prescribed in terms of "tapping" the container of powder a measured number of times, usually from a predetermined height. The method of "tapping" is best described as "lifting and dropping".

Bulk density and tapped density is reported in units such as g/cm³.