Relative Density

Relative Density 

Density is always calculated by dividing mass and volume.

Density is represented by the symbol - ρ (rho).

ρ = m / v

Relative density:

Relative density is the comparison of a substance's density with the density of the water at 4℃.

The other name for Relative Density is Specific gravity

Relative Density = Density of the substance (that we consider) / density of water at 4℃.

We consider the density of water at 4℃ for the comparison because water at 4℃ possess the highest density of water. To get a clear idea refer the following link.

Even though ice is a solid why does it have low density than water?

Density of water at 4℃ is 1000 kg/m³

Now, let us calculate the relative density of ethyl acetate.

1. The density of ethyl acetate is 902 kg/m³. Calculate the relative density of ethyl acetate.

Solution:

Relative Density = Density of the substance (that we consider) / density of water at 4℃.
of  a substance

Relative Density =  Density of the ethyl acetate / density of water at 4℃.
of ethyl acetate

Relative Density =  [902 kg/m³] / [1000 kg/m³]
of ethyl acetate

Relative Density =  0.902
of ethyl acetate

There is no units since it is a comparison.