1. DENSITY
Density is a central concept in chemistry and physical science.

2. Why is DENSITY Important?
Lava lamps
Floating boats
Hot Air Balloon

3. Why is DENSITY Important?
Density is a principle that is involved in many of Earth’s processes:
•Water Cycle
• Ocean currents and circulations
• Plate tectonics
• Weather (atmospheric temperature and pressure),….
Density help scientists to identify minerals and rocks.

4. What is Density?
•Density is the measurement of the compactness of an object.
Which is more dense a cube of wood or a cube of metal?
•As long as an object is made up of molecules, and thus has size, it has a density.
(Solid, Liquid, Gas)
•The density of a substance is the relationship between the mass of the substance and how much space it takes up (volume).

5. How Can I Calculate Density?
Density is defined by the ratio of the mass of a substance to its volume.
Mass- The amount of matter (stuff) in an object.
Units = grams (g)

6. How can I calculate density?
Density is defined by the ratio of the mass of a substance to its volume.
Volume- the amount of space that an object takes up
Units = centimeters cubed (cm3)

7. How can I calculate density?
Density is defined by the ratio of the mass of a substance to its volume.
Mass- The amount of matter (stuff) in an object.
Units = grams (g)
Volume- the amount of space that an object takes up
•Units = centimeters cubed (cm3)
Density-the amount of matter in a certain amount of space.
•Units = g/cm3

8. ALWAYS SHOW YOUR WORK AND REMEMBER UNITS!
How can I calculate density?
Density equals the mass of the substance divided by its volume.
𝐷𝑒𝑛𝑠𝑖𝑡𝑦= 𝑀𝑎𝑠𝑠 𝑉𝑜𝑙𝑢𝑚𝑒
𝐷= 𝑀 𝑉
Density equation:
Units = g/cm3
ALWAYS SHOW YOUR WORK AND REMEMBER UNITS!

9. Which one is more dense? How about this: Which square is more dense?
Objects with the same volume but different mass

10. Which one is more dense? Now which square is more dense? a. b.
Objects with the same mass but different Volume

11. A. D= 𝑽𝒐𝒍𝒖𝒎𝒆 𝑴𝒂𝒔𝒔 B. 𝑫= 𝑴𝒂𝒔𝒔 𝑨𝒓𝒆𝒂 C. 𝑫= 𝑴𝒂𝒔𝒔 𝑽𝒐𝒍𝒖𝒎𝒆
What is the equation of density?
A. D= 𝑽𝒐𝒍𝒖𝒎𝒆 𝑴𝒂𝒔𝒔
B. 𝑫= 𝑴𝒂𝒔𝒔 𝑨𝒓𝒆𝒂
C. 𝑫= 𝑴𝒂𝒔𝒔 𝑽𝒐𝒍𝒖𝒎𝒆

12. Let’s try a density problem together
Jonathan has a paper clip. It has a mass of 9g and a volume of 3cm3. What is its density?
Mia has an eraser. It has a mass of 3g, and a volume of 1cm3. What is its density?
Mass= 9 g
Volume= 3 cm3
Density = ?
Mass= 3 g
Volume= 1 cm3
Density = ?

13. Work on these problems with your neighbor.
Jared has a rock. The rock has a mass of 6g and a volume of 3cm3. What is the density of the rock?
Annika has a gel pen. The gel pen has a mass of 8g and a volume of 2cm3. What is the density of the pen?
9 g
2 cm3
2 g/cm3
0.25 g/cm3
4 g/cm3
4 g/cm2

14. Now, try these on your own.
Ariel has a watch. It has a mass of 4g and a volume of 2cm3. What is the density of the watch?
Avery has a wallet. It has a mass of 15g and a volume of 5cm3. What is the density of the wallet?

15. Super Scientist Question of the Day
Jake has a book, a ruler, and a balance.
How can Jake find the density of the book with the tools he has?

16. Liquid Layers
If you pour together liquids that don’t mix and have different densities, they will form liquid layers.
The liquid with the highest density will be on the bottom.
The liquid with the lowest density will be on the top.

17. Check out the layer density jar. Which layer has the highest density?
Liquid Layers
Check out the layer density jar. Which layer has the highest density?
Which layer has the lowest density?
Imagine that the liquids have the following densities:
A) 10g/cm3 B) 3g/cm3
C) 6g/cm3 D) 5g/cm3
Which number would go with which layer?

18. Six layers of density!!!! Rubbing alcohol 0.79 g/cm3
Vegetable oil g/cm3
Water is g/cm3
Milk g/cm3
Dawny dish soap g/cm3
Maple syrup g/cm3

19. Why do Icebergs float?
When water freezes, the molecules crystallize, with the space between each molecule increasing. If the mass of water does not change, this has the effect of decreasing the density of frozen water. It is for this reason that ice floats on top of water, as seen in the frozen surfaces of lakes and in icebergs.