1. What are the Factors that Affect Density?

2. What is Density Density – determines if something floats or sinks.
Objects that are less dense will float.
The amount of matter in an object.

3. Density Determines Floatation
Density – determines if something floats or sinks.
Saturn would float on water b/c its density is lower than water
The material in the core is the densest so it sank to the center of the Earth

4. What happens to the Density of a cube if it is cut in half?
Density of the original cube=
200 g/ (2cm x 5cm x 10cm)
= 2 g/cm3
100 g/ (2cm x 2.5cm x 10 cm)
If the Cube is cut in half the mass and the volume are cut in half so the density is still the same.
2cm
10cm
5cm
Mass = 200g

5. Factors that DO NOT affect density
Size
Shape
Size of the sample will not affect the density of the same material.
Shape of the samples does not affect the density of objects made of the same material
density
volume

6. Shape and size do not affect density because ….
The size and shape do not affect the packing of the molecules inside the object.
The arrangement of atoms inside the object is still the same even if the shape or size is changed

7. What are the Factors that Do Affect Density?
What would change the spacing of molecules in an object?

8. Pressure As pressure increases Density increases
Pressure squeezes the molecules together and decreases the volume of the object without decreasing the mass.
If I squeeze a slice of bread by adding pressure what would happen to the holes in the bread slice?

9. Temperature
As temperature increases Density decreases b/c the molecules vibrate and move away from each other.
Warm air rises in a room because warm air is less dense.
Cold air in a room will sink b/c it is more dense

10. Phase of Matter Solids – Most dense for every material except water.
** water in its solid form is less dense than its liquid form.
***Ice cubes (solid) float in Water.

11. Phase of Matter Liquid Gas
Particles are close together but the molecules have the ability to move. ** Water is densest in its liquid form (4˚C).
Least dense phase of matter.
Molecules furthest apart.

12. How does the Density affect the layering of Earth’s spheres?
Which is the least dense sphere???
Atmosphere

13. How does the Density affect the order of atmosphere layers?
Least Dense atmosphere layer
Densest layer

14. Black Holes Pull all matter in.
Scientists believe that black holes are created by massive objects that have such a large gravitational force they pull in all matter and light.
Black hole cartoon