How do you find the pounds per gallon of a chemical?

Finding the pounds per gallon of a chemical involves understanding the relationship between its specific gravity and the weight of water. Specific gravity is a dimensionless quantity that compares the density of a substance to the density of water, typically at 4 degrees Celsius where water has a density of approximately 1 g/cm³ or about 8.34 lbs/gallon at standard temperature and pressure.

To determine the pounds per gallon for a chemical, you multiply its specific gravity by the weight of a gallon of water, which is 8.34 lbs. This calculation gives you the weight of the chemical in pounds per gallon because it scales the weight of water according to the density of the chemical being assessed.

Using this method, if you had a chemical with a specific gravity of, say, 1.5, you would multiply 1.5 by 8.34 lbs/gallon to find that it weighs 12.51 lbs/gallon. This process accurately accounts for the difference in density between the chemical and water, providing a straightforward way to quantify the chemical's weight per volume.

Choices that suggest dividing the specific gravity by the weight of water or adding the specific gravity to the weight of water do not correctly represent the physical relationships between these properties. Similarly,