A specific gravity of 1.000 means that a substance has the same density as water at 4°C (39.2°F).

Here's a breakdown:

* Specific gravity is the ratio of the density of a substance to the density of a reference substance, which is usually water.

* Density is the mass per unit volume of a substance.

* Water at 4°C has a density of 1 gram per cubic centimeter (g/cm³).

Therefore, if a substance has a specific gravity of 1.000, it means its density is also 1 g/cm³.

Examples:

* Pure water at 4°C has a specific gravity of 1.000.

* A substance with a specific gravity greater than 1.000 is denser than water and will sink in water.

* A substance with a specific gravity less than 1.000 is less dense than water and will float in water.

Note: Specific gravity is a dimensionless quantity as it is a ratio of two densities.