Sink of Float Lab

Total Points: _____/34
Math Time!!
List some appropriate units to measure mass.
Today we will use 2 methods to calculate an object’s volume:
Method 1: Use a ruler (objects with a definite shape)
__________ X __________ X __________ = Volume (mL or cm3)
Example: What is the volume of an object 10cm long, 5cm wide, and 2cm high?
Method 2: water displacement (objects with an irregular shape)
When you place an object in water, the water level will rise an equal amount to the
volume of the object. In order for this to work, the object must be completely submerged
(under) in the water.
Step 1: Pour water into a graduated cylinder. Record the water level.
Step 2: Place the object in the cylinder. The water level will rise. Record the new water
Step 3: Subtract the volume of the water from the volume of the water plus the object.
The difference is the volume of the object.
Example: You fill a graduated cylinder with 10 mL of water. When you add a marble,
the water level rises to 13 mL. What is the volume of the marble?
Calculating Density
Density is how tightly atoms are packed into a given volume. No matter the size of the
substance, it will always have the same density. For example, the density of a bottle of
water is 1g/mL and the density of a gallon of water is 1 g/mL.
__________ = Density
Suppose you know the mass of an object is 30g and its volume is 15 cm3. What is its
density? Use the correct units.
Total Points: _____/34
In your lab group, you will calculate the mass, volume, and density of each object (2 pts
Sink or
(mL or cm3)
(g/mL or g/cm3)
1. Iron
2. Styrofoam
3. Clay
Analysis Questions: (2 pts each)
1. The density of water is __________ g/mL.
Matter with a density greater than water will __________.
Matter with a density less than water will __________.
2. A stone is placed in a graduated cylinder, which has been filled to the 35 mL
mark. The level rises to 42 mL. What is the volume of the stone?
3. You have a metal bar. Its mass is 57.9g and its volume is 3 cm3. What is its
4. If you cut the mentioned bar in half, what would be the density of each half?
5. The density of cork is .24g/cm3. If you place it in water, will it sink or float?
Total Points: _____/34
1. Read pages 190 and 191. Label the diagram of the Earth’s interior above. (9 pts)
a. Color code the 3 layers
b. Include the layers composition (what elements is it made of?)
c. Give the percent of the Earth’s mass made up by each layer.
2. For the lab materials, identify the layer(s) of the Earth they represent.
a. Crust:
b. Mantle:
c. Core:
3. Now that you know the Earth is made of 3 materials from the lab, estimate the
density of the Earth. Be sure to explain your answer and show your work.
4. Order the layers of the Earth from most dense to least dense.
5. If the mass of the Earth is 5.97 x 1027 g and the volume is 1.08 x 1027 mL, what is
the density of the Earth?
6. Going Beyond: Calculate your percent error:
Actual density – experimental density x 100 =
Actual density