1. Density

2. Demos for this lecture 1 kg mass (Is it heavy?) 50 ml of alcohol and 50ml of water in graduated cylinders on a double pan balance.

3. Density Density is how compact matter is. More mass shoved into a certain amount of space makes something more dense.

4. Density Considers Two Things How much mass is present. How much volume does it take up. Make sure to consider both these factors when discussing density.

5. A A

6. A A 1.What does Figure A illustrate about density?

7. A A 2. What does Figure B illustrate about density?

8. A A 3. If the cube of aluminum in figure B were cut into four equal parts. How would the density of one part compare to the whole cube ?

9. A A 4. Metals expand when heated. If the gold cube in part B is heated, what will happen to its density?

10. Does it Float? If something floats or rises it is less dense than the material it is floating/rising in. Objects of greater density will sink.

14. Density Density is the mass per unit volume. –How much mass there is in a certain amount of space.

15. Density Density is the mass per unit volume. Density = Mass ÷ Volume

16. Density Density is the mass per unit volume. D = Mass ÷ Volume ÷

17. Solving For Variables

18. Common Volume Units

19. Illegal ivory is often detected on the basis of density. What is the density of the elephant tusk? Mass = 2680g Volume = 1450cm 3

20. Illegal ivory is often detected on the basis of density. What is the density of the elephant tusk? Mass = 2680g Volume = 1450cm 3 D = M ÷ V = 2680g ÷ 1450cm 3 = 1.8482g/cm 3 = 1.85g/cm 3

21. Calcium chloride is used as a deicer on roads in winter. Its density is 2.50g/cm 3. What mass of calcium chloride will the truck hold if its volume is 4560L?

22. 4560L = 4,560,000cm 3

23. Calcium chloride is used as a deicer on roads in winter. Its density is 2.50g/cm 3. What mass of calcium chloride will the truck hold if its volume is 4560L? 4560L = 4,560,000cm 3 M = D x V = 2.50g/cm 3 x 4,560,000cm 3 = 11,400,000g

24. The density of methanol is 0.788g/cm 3. What is the minimum volume of a tank that can hold 795kg of methanol.

25. 795kg = 795,000g

26. The density of methanol is 0.788g/cm 3. What is the minimum volume of a tank that can hold 795kg of methanol. 795kg = 795,000g V = M ÷ D = 795,000g ÷ 0.788g/cm 3 = 1,008,883cm 3 = 1,010,000cm 3 How many liters is this?

27. The density of methanol is 0.788g/cm 3. What is the minimum volume of a tank that can hold 795kg of methanol. 1,010,000cm 3 ÷ 1000 cm 3 /L = 1010L

28. Homework Worksheet: Chapter 2-3