Density

• a physical property of matter that describes the ration of mass to volume.

Density = Mass/Volume

                 possible units: g/mL, g/L, g/cm^3, Kg/L

1cm^3 = 1mL

Float vs. Sink experiment

Density of Liquid > Density of object                  Float

Density of Liquid < Density of object                  Sink

For example:
       Say there is a filled water balloon filled with an unidentifiable liquid.  There is 350mL with a mass of 450g.  What is the density of the liquid in the balloon?

D= M/V
D= 450/350
= 1.28mL/g

WORD PROBLEMS

1.  A block of aluminum occupies a volume of 15.0 mL and weighs 40.5 g. What is its density?

2.  Mercury metal is poured into a graduated cylinder that holds exactly 22.5 mL. The mercury used to fill the cylinder weighs 306.0 g. From this information, calculate the density of mercury.

3.  What is the weight of the ethanol that exactly fills a 200.0 mL container?

 The density of ethanol  is 0.789 g/mL.

4.  A rectangular block of copper metal weighs 1896 g. The dimensions of the block are 8.4 cm by 5.5 cm by 4.6 cm. From this data, what is the density of copper?  (hint:  find the volume of a block first)

5. What volume of silver metal will weigh exactly 2500.0 g. The density of silver is 10.5 g/cm³.

6. Find the mass of 250.0 mL of benzene. The density of benzene is 0.8765 g/mL.

7.  A block of lead has dimensions of 4.50 cm by 5.20 cm by 6.00 cm. The block weighs 1587 g. From this information, calculate the density of lead.

8. 28.5 g of iron shot is added to a graduated cylinder containing 45.50 mL of water. The water level rises to the 49.10 mL mark, From this information, calculate the density of iron.

Answers

1) 2.70g/mL

2) 13.6g/mL

3)  253g

4) 8.922g/cm^3

5) 238 cm^3

6) 219.1 g

7) 11.3g/cm^3

8)7.92g/mL