Difference Between Density and Bulk Density

Density vs Bulk Density

Density and bulk density are properties of matter, which are very important when it comes to the study of properties of matter. These are defined for substances such as air, gas or solids, in many forms. Density and bulk density are widely used attributes when it comes to fields such as chemistry, physics, material science and construction engineering. In this article, we are going to discuss what density and bulk density are, and their definitions, applications and differences.

Density

Density is defined for substances such as liquids, gases and solids. It is a very useful property when determining the buoyancy of materials on one another. The density is a simple idea of how closely packed the molecules of substances are, and how much a molecule weighs. The density is defined as the ratio of the mass of a substance to the volume occupied by that mass. For any gas, the molar volume (the volume occupied by a mole of molecules) in a given temperature and pressure is constant. Therefore, the density of a gas at a given pressure and temperature is directly proportional to the molecular weight of that gas. The terms relative density and specific gravity are used to compare the densities of two given substances. They are dimensionless quantities, displaying the ratio between two densities. In some cases, the density is also defined as the weight of a given volume divided by the volume. It is usually known as apparent density.

Bulk Density

Bulk density is a very important characteristic of substances such as powders, granules, and other particles like solid substances. Bulk density is defined as the mass of a bulk material divided by the volume occupied by that material. To understand this concept of bulk density, one must first understand what bulk materials are. Bulk materials are substances such as powders, precipitates, crystals or even gelatin materials. The basic property of bulk materials is that, the bulk materials have pockets of other materials such as air, water or even some other materials. The bulk density of a given substance greatly varies on the condition the material is in. A closely packed sample of a material would have a higher bulk density than a normally poured sample. This concept is very important in chemistry. Therefore, bulk densities are categorized into two, they are freely settled bulk density, also known as poured bulk density, which is taken without any disturbance to the poured material, and the tapped density, which is recorded after a certain procedure of packing the substance.