Density, Volume and Mass

Question

3. A metal weighing 7.101 g is placed in a graduated cylinder containing 33.0 mL of water. The water
level rose to the 37.4 mL mark.
a) Calculate the density of the metal (in g/mL).
b) If you were to do this with an equal mass of aluminum (d = 2.7 g/mL), how high would the water rise?

Answer 1

To calculate the density using water displacement, there are two steps needed for part A.

 

First Step:

Volume of metal sample= Final Volume - Initial Volume

Volume of metal= 37.4 mL - 33.0 mL = 4.40 mL

 

Second step:

Density= mass/ volume

Density= 7.101 g/ 4.40 mL = 1.61 g/mL

 

For part B, we are going in reverse.

 

First step, finding the volume of the metal=

Volume= mass/ Density

Volume= 7.101 g/ 2.7 g/mL= 2.63 mL

 

So, the water would have risen 2.63 mL when the aluminum sample would have been added.