specific gravity
Noun: - The ratio of the density of a substance to the density of a reference substance (typically water at 4°C): Specific gravity is a dimensionless quantity that compares how dense a material is compared to water. It indicates whether a substance will float or sink in water.
Specific gravity is used as a property to characterize materials, especially in science and industry. It is a key measurement in fields like chemistry, geology, and fluid mechanics. - It is typically used with the verb "to have" or "to measure." - It is often followed by "of" to specify the substance (e.g., the specific gravity of iron).
- The specific gravity of pure gold is approximately 19.3, meaning it is about 19.3 times denser than water.
- To identify the mineral, the geologist measured its specific gravity.
- A substance with a specific gravity less than 1.0 will float in water.
- "Apparent specific gravity": The specific gravity of a porous material, including its pores.
- "True specific gravity": The specific gravity of the solid material itself, excluding any pores or voids.
- Density (n): Mass per unit volume (e.g., kg/m³). While density is an absolute measurement, specific gravity is a relative, dimensionless comparison.
- Relative density: A synonym for specific gravity.
- Relative density
Specific gravity is a pure number with no units because it is a ratio of two densities. For liquids and solids, the reference is usually pure water at 4°C (where its density is greatest, at 1 g/cm³). For gases, the reference is often dry air at standard temperature and pressure.
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the density of a substance relative to the density of water
