The ratio of the mass of a solid or liquid to the mass of an equal volume of distilled water at 4°C (39°F) or of a gas to an equal volume of air or hydrogen under prescribed conditions of temperature and pressure. Also called relative density. the weight of a substance divided by the weight of the amount of water that would fill the same space. or relative density Ratio of the density of a substance to that of a standard substance. For solids and liquids, the standard substance is usually water at 39.2°F (4.0°C), which has a density of 1.00 kg/liter. Gases are usually compared to dry air, which has a density of 1.29 g/liter at 32°F (0°C) and 1 atmosphere pressure. Because it is a ratio of two quantities that have the same dimensions (mass per unit volume), specific gravity has no dimension. For example, the specific gravity of liquid mercury is 13.6, because its actual density is 13.6 kg/liter, 13.6 times that of water
The weight of a material compared to the weight of an equal volume of water is an expression of the density (or heaviness) of a material Insoluble materials with specific gravity of less than 1 0 will float in (or on) water Insoluble materials with specific gravity greater than 1 0 will sink in water Most (but not all) flammable liquids have specific gravity less than 1 0 and, if not soluble, will float on water--an important consideration for fire suppression
The ratio of density of a given liquid to that of pure water Specific gravity is used to measure the salinity of seawater as compared to distilled water Distilled water has a specific gravity of 1 000 while natural seawater has a S G of about 1 025
In the case of liquids, the ratio between the weight of equal volumes of water and another substance measured at standard temperature, where the weight of the water is assigned the value 1
Specific Gravity is the ratio of the density of a material to the density of water The density of water is about 1 gram per cubic centimeter (g/cc) Materials which are lighter than water (specific gravity less than 1 0) will float Most materials have specific gravities exceeding 1 0, which means they are heavier than water and will sink Knowing the specific gravity is important for planning spill clean-up and fire fighting procedures For example, a light flammable liquid such as gasoline may spread and if ignited burn on top of a water surface
A comparison of the weights of equal volumes of a given liquid and water A ceramic slurry with a specific gravity of 1 8 is thus 1 8 times heavier than water The best way to measure specific gravity is to weigh a container and record its weight, then weigh the container full of water and then full of the liquid of unknown specific gravity Subtract the weight of the container from each weight and divide the weight of the liquid being measured by the weight of the water
The ratio of the weight of any volume to the weight of an equal volume of another substance taken as a standard For solids or liquids, the standards are usually water and for gases the standard is air
The ratio of the weight of a substance to the weight of an equal volume of distilled water at 4oC Water at that temperature has a specific gravity of 1 If the specific gravity of the other substance is greater than 1 it floats in water; if less than 1 it sinks