Density Calculations – Worked Example Problem


Rainbow Density Column
Density Column where the different layers are solutions of different densities. Less dense at the top, more dense at the bottom.

Density is the measurement of the amount of mass per unit volume. Density calculations are done using the formula:


where
ρ = density
m = mass
V = volume

Example Problems:
1. Calculate the density in g/mL of 30 mL of solution that weighs 120 grams.
2. Calculate the density in g/mL of 0.4 L of solution weighing 150 grams.
3. Calculate the density in g/mL of 3000 mL of solution weighing 6 kg.

Example 1

density = 4 g/mL

Example 2
We want to know the density in g/mL, but our volume is in liters. First, convert the volume to mL.


V= 400 mL

Now we can calculate the density

ρ = 0.375 g/mL

Example 3
Again, we want g/mL, and our mass is in kg. Convert the mass to grams.


m = 6000 grams

Calculate density

ρ = 2 g/mL