**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