What units should be used when describing the density of oil?

Generally, density is measured using he SI unit for measurement of density which is kg/m³ or the cgs units used to describe the density of a substance which is g/cm³

However, due to its nature (being composed of varying amount proportions of different compounds mixed together resulting in a variation of the density of naturally produced crude oil) of having different densities whereby the lighter oils are more easily processed than the heavier variety of oils, oil density is related to the quality of the oil and it is usually measures in API gravity as follows;

°API = (141.5/S.G.) - 131.5

Where;

API = American Petroleum Institute

S. G. = Specific gravity

As such the API gravity of fresh water with a S. G. of 1.0 has is 10 degrees

Explanation: