Specific gravity is defined as

Specific gravity is defined as

• A. Weight of a particle relative to the weight of an equal volume of water
• B. Density of water at room temperature
• C. Mass per area
• D. Weight of a particle relative to a solvent other than water

Answer: (D)

Specific gravity is the ratio that compares how heavy a given volume of a substance is to the weight of the same volume of a reference liquid. This makes SG a dimensionless number because the volumes cancel, leaving a pure ratio of weights (or, equivalently, densities). The key idea is not tied to any particular solvent—the reference liquid can be water, but conceptually SG is defined relative to a solvent. In practice, water is the common reference used in many water-treatment contexts, which is why you often see SG described with water as the reference. The statement that best captures the general definition is that you compare the weight of a particle to the weight of the same volume of a solvent (not necessarily water); the result tells you how dense the particle is in relation to that solvent. This helps explain why heavier particles sink in water, while lighter ones may float or remain suspended. The other descriptions describe related quantities (like the density of water or mass per area) but do not convey the ratio of weights to a reference liquid.

Specific gravity is the ratio that compares how heavy a given volume of a substance is to the weight of the same volume of a reference liquid. This makes SG a dimensionless number because the volumes cancel, leaving a pure ratio of weights (or, equivalently, densities). The key idea is not tied to any particular solvent—the reference liquid can be water, but conceptually SG is defined relative to a solvent. In practice, water is the common reference used in many water-treatment contexts, which is why you often see SG described with water as the reference. The statement that best captures the general definition is that you compare the weight of a particle to the weight of the same volume of a solvent (not necessarily water); the result tells you how dense the particle is in relation to that solvent. This helps explain why heavier particles sink in water, while lighter ones may float or remain suspended. The other descriptions describe related quantities (like the density of water or mass per area) but do not convey the ratio of weights to a reference liquid.