Question

A rock weighing 15.0g is placed in a graduated cylinder, displacing the volume from 25.0 mL to 36.2 mL. What is the density of the rock in grams/cubic centimeter?

Answer 1

Answer : The density of the rock is, $1.339g/cm^3$

Explanation : Given,

Mass of the rock = 15 g

Initial volume = 25 ml

Increased volume = 36.2 ml

First we have to calculate the volume of the rock.

Volume of rock = Increased volume of water - Initial volume of water

Volume of rock = 36.2 ml - 25 ml = 11.2 ml

Now we have to calculate the density of rock.

Formula used :

$Density=\frac{Mass}{Volume}$

Now put all the given values in this formula, we get the density of the rock.

$Density=\frac{15g}{11.2ml}=1.339g/ml=1.339g/cm^3$

Conversion : $1ml=1cm^3$

Therefore, the density of the rock is, $1.339g/cm^3$

Answer 2

Density is defined as mass/volume, and the volume is 36.2-25 mL
so just substitute into the equation to get the answer. 

Hope this helps.