1. 10/15/2015 Starter : 10/15/2015 67 68 Density Practice: Glue notes here Connection: Density Ws Exit: Jake has a book, a ruler, and a balance. How can Jake find the density of the book with the tools he has? Application : Do the Practice Density Problems here EQ: How can density be measured or quantified? Ms. Kraft found a cube with the following measurements: L=3cm W=5cm H=4 cm. What is the volume of the cube? The cube has a mass of 162 g. How does this relate to density?

2. Agenda 1. Starter 2. Density Notes 3. Exit

3. DateLecture/ Activity/ Lab Page 8/29/ Syllabus /Notebook Guidelines 1-2 8/29 Periodic Table/ Formula3-4 8/29 Tools/ Measurement 5-6 8/29 Lab Report/ Investigations7-8 8/30 Safety equipment 9-10 8/31 Flow of energy vocabulary 11-12 9/4 Matter, Metals, Nonmetals, & metalloids13-14 9/5 Lab- Physical Properties15-16 9/6 Density 17-18 Table of Contents

4. Calculating Density

5. Density We know that matter is anything that occupies a space and has mass. Density is the amount of matter there is in a given space.

6. Examples Metal vs. Wood Metal Wood Water vs. Oil Water Oil The amount of particles there are in the metal and water that occupies the space provided is a lot more than the amount of particles present in the oil and wood in the same amount of space. Water and metal are more dense.

7. What do we use density for? Density is one of the basic ways to measure and compare the physical properties of different matter

8. Which one is more dense? People in a square (popular place vs. not popular place) How about this: Which square is more dense? A B Do they occupy the same volume? Do the have the same amount of particles?

9. Which one is more dense? Now which one is more dense? Do they occupy the same volume? Do the have the same amount of particles? B A

10. A is more dense because for the small volume it holds, it has more matter. Even though they have the same amount of particles, if A was the same size as B, A would have 4 times as much particles. B A A A A A

11. What is density? To find density, the amount of mass is divided by the volume of the substance. Density = mass OR mass ÷ volume. volume

12. Mass is measure in grams and kilograms. Volume is measure in cubic centimeters or cubic milliliters.

13. Mass Grams is represented as a g Kilograms is represented as a kg Volume Solid -------Cubic centimeters = cm 3 Liquid ------ milliliters = mL  1mL = 1cm 3 ALWAYS REMEMBER UNITS!

14. So if Density = mass volume Density = g or g cm 3 mL

15. SI Units: International System of Units Modern metric system, measurements Mass Grams = g Kilograms = kg Length Meter = m Millimeter = mm Liquid Liters = L Milliliter = mL ALWAYS REMEMBER UNITS!

16. SI Units: continued Time Seconds = s Milliseconds = ms Conversions  Milli = m __  centi=c __  Kilo =k __ ALWAYS REMEMBER UNITS!

17. Frank measured an eraser. He used a balance to measure the mass at 4g. However Frank is having trouble finding the volume. Can you help him? l = 5cm w = 1cm h = 2 cm Given: Formula Solve: Answer: L = 5 cm w = 1 cm h = 2 cm V= 5 cm x 1 cm x 2 cm = 10 cm 3 10 cm 3 ALWAYS REMEMBER UNITS!

18. Let’s try a density problem together Frank has a paper clip. It has a mass of 9g and a volume of 3cm 3. What is its density? Given: D = m = V = Formula: Solve: Answer: ? 9 g 3 cm 3 D = m / V = 9 g / 3 cm 3 = 3 g / cm 3 3 g / cm 3 ALWAYS REMEMBER UNITS!

19. Frank also has an eraser. It has a mass of 4g, and a volume of 2cm 3. What is its density? Given: Formula Solve: Answer: D = ? m =4 g V =2 cm 3 D = m / v = 4 g / 2 cm 3 = 2 g / cm 3 2g / cm 3 ALWAYS REMEMBER UNITS!

20. Work on these problems with your neighbor. Jack has a rock. The rock has a mass of 6 g and a volume of 3 cm 3. What is the density of the rock? Jill has a gel pen. The gel pen has a mass of 8 g with a volume of 4 cm 3. What is the density of the rock? 2 g / cm 3 2 g / cm 3

21. Now, try these on your own. Alicia has a watch. It has a mass of 4 g and a volume of 2 cm 3. What is the density of the watch? Mia has a wallet. It has a mass of 15 g and a volume of 5 cm 3. What is the density of the wallet? 2 g / cm 3 3 g / cm 3

22. To actually calculate density we need measuring instruments. If we use a scale, we measure the weight of the object. The weight is the force due to gravity pulling down. You weigh less on the moon because gravity is less. But the amount of particles you are made of doesn’t change. So to measure the mass, we need to use a balance

23. Only mass is measured by the balance because the object’s mass counteract with the weights on the balance.

24. Measuring the volume of an object can be very tricky as well. Most objects are not regular shapes that we have formulas for to calculate the volume. Such as:

25. In real life, most objects only resemble these shapes. Most objects are odd shaped. It is almost impossible to accurately calculate the volume of most objects.

26. That’s where volume by displacement comes into play. When you think of displacement, what do you think of?

27. The object takes a certain amount of space. The water particles rises to a new final volume. The difference in the water levels from before and after will give you the volume of the object. In volume by displacement, the displacement of water or any other liquid is involved. In a graduated cylinder, we measure the initial volume of water. Then we drop our object in. V1V1 VFVF

28. The equation for volume of displacement Object Volume = Water Volume After – Water Volume Before 75-mL – 50-mL = Object’s volume 25-mL = Object’s volume

29. What is the volume of this object? V o = ? V f = V i = V o = 9 mL 7 mL 9mL – 7mL 2mL

30. Measuring Accuracy When measuring Volume of liquids we use the: Meniscus: Bottom arch water of used for measuring volume.

31. Liquid Layers If you pour together liquids that don’t mix and have different densities, they will form liquid layers. When liquids don’t mix that means they are Insoluble

32. Liquid Layers The liquid with the highest density will be on the bottom. The liquid with the lowest density will be on the top.

33. Liquid Layers Which layer has the highest density? Which layer has the lowest density? The green solution The yellow solution

34. Liquid Layers Imagine that the liquids on the left have the following densities: A. 10g/cm 3 C. 3g/cm 3 B. 6g/cm 3 D. 5g/cm 3 Which density would go with which layer? A B D C

35. Liquid Layers – Try with your neighbor Which liquid has the highest density? Which liquid has the lowest density? Which liquid has the middle density? The Golden Syrup The Oil The Water

36. Liquid Layers – Try on your own! Imagine that the liquids on the right have the following densities: 15 g / cm 3 10 g / cm 3 3 g / cm 3 9 g / cm 3 7 g / cm 3 12 g / cm 3 Match the colors to the correct densities. 3g/cm 3 7g/cm 3 9g/cm 3 10g/cm 3 12g/cm 3 15g/cm 3

37. 10/15/2015 Starter : 10/15/2015 67 68 Density Practice: Glue notes here Connection: Density Ws Exit: Jake has a book, a ruler, and a balance. How can Jake find the density of the book with the tools he has? Application : Do the Practice Density Problems here EQ: How can density be measured or quantified? Ms. Kraft found a cube with the following measurements: L=3cm W=5cm H=4 cm. What is the volume of the cube? The cube has a mass of 162 g. How does this relate to density?