Calculation of Specific Gravity
Specific Gravity = ratio of the density (mass of a unit volume) of a substance to the density (mass of the same unit volume) of a reference substance.
Formula:
Specific Gravity = Weight of substance / Weight of an equal volume of water
Example:
What is the specific gravity of a substance that weights 75 g and occupies a volume of 150 mL?
SG = Weight of substance / Weight of an equal volume of water
SG = 75 g / 150 g
SG = 0.5
What is the volume of a solution that weighs 450g and has a specific gravity of .75?
SG = Weight of substance / Weight of an equal volume of water
0.75 = 450g / X
X = 450 g / 0.75
X = 600 mL