1. Density
PG. 17

2. Comparing Feathers and Rocks
Which would have the greater mass?
Which would have the greater volume?

3. Density Density is defined as mass per unit volume
Density is a measure of how tightly packed molecules are in an object
Basically it is the amount of
matter within a certain volume

4. The Math The Units: Mass= Grams (g) Volume (2 ways) Ruler= cm3
Displacement= mL
Density (2 ways)
Ruler= g/cm3
Displacement= g/mL

5. ____________________
DMV Triangle
Cover the variable that you need to find, the triangle will tell you what math to do to find it. m
v d
____________________

6. What is Density?
If you take the same volume of different substances, then they will weigh different amounts.
Which of these is the most dense?
Iron! It has the most mass for its volume

7. Density for Different Things
Each substance has it’s own density
It does not matter how much of a substance you have, it will have the same density
1 gram of water will have the same density as 100 grams of water
Distilled water has a density of 1 g/cm3 (MEMORIZE this)
Objects with different densities interact in a very predictable way…the more dense object will sink, the less dense will rise to the top

8. Practice Problem
What is the density (g/cm3) of a 48 g of a metal if the metal raises the level of water in a graduated cylinder from 25 mL to 33 mL?
A) 0.2 g/cm3 B) 6 g/cm3 C) 252 g/cm3

9. Density Problems—USE DMV TRIANGLE
If 52 grams of matter has a volume of 65 cm3, what is the density of the matter? Will it float or sink in water?
If an object has a mass of 810 g and a volume of 45 cm3, what is its density? Will it float or sink in water?
When you add a rock to 70 mL of water in a graduated cylinder, the water rises to 80 mL. The density of the rock is 4.2 g/cm3. What is the rock's mass?
What is the volume of a sample of liquid with a density of 20 g/cm3 and a mass of 25 g?
A 540g fish displaces 90 cm3 of water. What is the density of the fish?