Answer: The density of unknown substance is 2.43 g/mL
Step-by-step explanation:
Density is defined as the ratio of an object's mass and volume.
To calculate density of a substance, we use the equation:

We are given:
Mass of unknown substance = 56.8 g
Volume of unknown substance = 23.4 mL
Putting values in above equation, we get:

Hence, the density of unknown substance is 2.43 g/mL