Question

Define relative density​

Answer 1

Answer:

The ratio of the density of a substance to the density of a standard substance under specified conditions.

For liquids and solids the standard is usually water at 4°C or some other specified temperature.

Answer 2

Answer:

the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest (at 4 °C or 39.2 °F); for gases, the reference is air at room temperature (20 °C or 68 °F). The term "relative density" is often preferred in scientific usage.