Chemistry help.

Question

A rock weighing 30.0 g is placed in a graduated cylinder displacing the volume from 22.3 mL to 27.6 mL. what is the density of the rock in grams/cubic centimeter?

 

D=M/V

M=DxV

V=M/D

Answer 1

The volume displaced = the volume of the rock.  Look up and read about Archimedes Principle.

Thus, volume of rock = 27.6 ml - 22.3 ml = 5.3 ml.  Also recall that 1 ml = 1cm³

Density = 30.0 g/5.3 cm³ = 5.66 g/cm³ = 5.7G/ cm³

I've reported the answer to 2 significant figures based on subtracting the volumes and using 1 decimal place (5.3 ml has 2 significant figures).