1. Density is the ratio of the mass of an object to its volume.
3.4
Determining Density
Density is the ratio of the mass of an object to its volume.

2. 3.4
Determining Density
Density is an intensive property that depends only on the composition of a substance, not on the size of the sample.

3. So, the density for a given substance defines the relationship between mass and volume
Like any relationship, it gives you 2 conversion factors
For gold,
19.3 g/cm3 and 1 cm3/19.3 g

4. 3.4
Determining Density
The density of corn oil is less than the density of corn syrup. For that reason, the oil floats on top of the syrup.
Because of differences in density, corn oil floats on top of corn syrup.

5. 46
A student finds a shiny piece of metal that she thinks is aluminum. In the lab, she determines the metal has a volume of 245 cm3 and a mass of 612 g. Is this metal aluminum?

6. Well, we can find the density of the material and compare it to the density in the table for aluminum and see if they match.
612 g = g
245 cm cm3
From the table, the density of aluminum is 2.70 g/cm3, so no the metal is not pure aluminum

7. Density and Temperature
3.4
Density and Temperature
Experiments show that the volume of most substances increases as the temperature increases. Meanwhile, the mass remains the same. Thus, the density must change.
The density of a substance generally decreases as its temperature increases.

8. for Sample Problem 3.10
Problem Solving 3.47 Solve Problem 47 with the help of an interactive guided tutorial.

9. 3.11

10. 3.11

11. 3.11

12. 3.11

13. for Sample Problem 3.11
Problem Solving 3.48 Solve Problem 48 with the help of an interactive guided tutorial.

14. 3.4 Section Quiz
1. If 50.0 mL of corn syrup have a mass of g, the density of the corn syrup is
0.737 g/mL.
0.727 g/mL.
1.36 g/mL.
1.37 g/mL.

15. 3.4 Section Quiz
2. What is the volume of a pure gold coin that has a mass of 38.6 g? The density of gold is g/cm3.
0.500 cm3
2.00 cm3
38.6 cm3
745 cm3

16. 3.4 Section Quiz
3. As the temperature increases, the density of most substances
increases.
decreases.
remains the same.
increases at first and then decreases.