Differentiate between density and relative density of a substance?

Density and relative density (also known as specific gravity) are two related but distinct concepts used to describe the mass and heaviness of a substance. Here's how they differ:

Density:

Density is an absolute measure of how much mass is contained within a given volume of a substance.
It is typically expressed in units such as kilograms per cubic meter (kg/m³), grams per cubic centimeter (g/cm³), or pounds per cubic inch (lb/in³).
The formula for density is: Density (ρ) = Mass (m) / Volume (V), where ρ is the density, m is the mass, and V is the volume.
Density provides information about the intrinsic properties of a substance, regardless of its surroundings or the reference substance.
Relative Density (Specific Gravity):

Relative density, also known as specific gravity, is a dimensionless ratio that compares the density of a substance to the density of a reference substance (usually water) at a specific temperature and pressure.
It is often represented as a ratio or a decimal number, with no units.
The formula for relative density is: Relative Density (RD) = Density of Substance / Density of Reference Substance.
Water is commonly used as the reference substance, so the specific gravity of water at a specific temperature and pressure is defined as 1. Therefore, if the relative density of a substance is greater than 1, it is denser than water, and if it is less than 1, it is less dense than water.
Relative density is useful for comparing the density of one substance to another and is often used in industries like chemistry, metallurgy, and brewing, where the relative density of solutions or materials is important.
In summary, density is an absolute measure of mass per unit volume, while relative density (specific gravity) is a dimensionless comparison of the density of a substance to the density of a reference substance (usually water). Relative density provides a convenient way to express the heaviness or density of a substance relative to another substance.