## Tapped Bulk Density Calculator

Tapped Bulk Density: g/ml

## Determination of Bulk and Tapped Densities

A technique to ascertain the bulk densities of pharmaceuticals that are in powder form under loose and tapped packing circumstances, respectively, is called "Determination of Bulk and Tapped Densities."

Loose packing is defined as the state that results from pouring a powder sample into a container without allowing it to consolidate, and tapped packing is defined as the state that results from repeatedly dropping the container carrying the powder sample a predetermined distance at a constant drop rate until the apparent volume of the sample in the container approaches unity.

## Bulk density of a powder

The ratio between the mass of an untapped powder sample and its volume, including the contribution of the inter particulate void volume, is the bulk density of a powder.

As a result, the powder particles' density and spatial arrangement in the powder bed affect the bulk density. Because measurements are done using cylinders, the bulk density is reported in grams per milliliter (g/mL), even though the international unit is kilogram per cubic meter (1 g/mL = 1000 kg/m3). There is also a gram per cubic centimeter (g/cm3) unit of measurement.

## Tapped density of a powder

The tapped density is a higher bulk density obtained mechanically by tapping a powder sample container.

Mechanically tapping a graduated measuring cylinder or vessel containing the powder sample yields the tapped density.

Following the initial powder volume or mass observation, the measuring cylinder or vessel is mechanically tapped, and volume or mass readings are taken until there is little further volume or mass change detected.

Mechanical tapping is accomplished by elevating the cylinder or vessel and allowing it to descend a given distance under its own mass using one of three ways outlined below. Devices that spin the cylinder or vessel while tapping may be preferable to minimize mass separation when tapping down.