1. Density Chapter 5 Section 2

2. Density A physical property that describes the relationship between mass and volume The amount of matter in a given space or a certain volume Inside a Golf Ball Inside a Ping Pong Ball More mass = More Density

3. Density of Solids Which would you rather carry? 1 Kilogram of feathers or 1 Kilogram of lead? 1 Kilogram = 2.2 pounds Larger bundle because feathers are less dense. More dense, so smaller bundle. Same mass! So no heavier!

7. Density of Liquids

8. http://www.stevespanglerscience.com/content/experiment/seven-layer-density-column Why do we end up with the results we have? The same amount of two different liquids will have different weights because they have different masses. The liquids that weigh more (have a higher density) will sink below the liquids that weigh less (have a lower density). Low Density High Density

9. Solving for Density D = mVmV To find an object’s density (D), first measure its mass (m) and volume (V). Then, use the equation below: Units for density are a mass unit divided by a volume unit. g/cm 3, g/mL, kg/m 3, and kg/L The density of a solid should be given in units of g/cm 3 or kg/m 3.

11. Practice What is the density of an object that has a mass of 350 g and a volume of 25 cm ? 3 3 3

12. Practice 2 A piece of wood that measures 5.0 cm by 5.0 cm by 5.0 cm has a mass of 80.0 grams. What is the density of the wood?

13. Practice 2 A piece of wood that measures 5.0 cm by 5.0 cm by 5.0 cm has a mass of 80.0 grams. What is the density of the wood?

14. Solving for Density D = mVmV What is the density of an object whose mass is 25 g and whose volume is 10 cm 3 ? D = 25 g 10 cm 3 D = 2.5 g/cm 3 The formula can be rearranged to find mass and volume: m = D x V V = mDmD

15. Solving for Density D = mVmV m = D x V V = mDmD Suppose that you have a lead ball whose mass is 454g. What is the ball’s volume? Substance Density at 20ºC and 1.0atm (g/cm 3 ) Substance Density at 20ºC and 1.0atm (g/cm 3 ) Helium (gas)0.00001663Zinc (solid)7.13 Oxygen (gas)0.001331Silver (solid)10.50 Water (liquid)1Lead (solid)11.35 Pyrite (solid)5.02Mercury (liquid)13.55 V = 454g 11.35g/cm 3 V = 40 cm 3

16. Solving for Density D = mVmV m = D x V V = mDmD What is the mass of a 15 mL sample of mercury? Substance Density at 20ºC and 1.0atm (g/cm 3 ) Substance Density at 20ºC and 1.0atm (g/cm 3 ) Helium (gas)0.00001663Zinc (solid)7.13 Oxygen (gas)0.001331Silver (solid)10.50 Water (liquid)1Lead (solid)11.35 Pyrite (solid)5.02Mercury (liquid)13.55 m = 13.55g/mL x 15mLm = 203g

17. Solving for Density D = mVmV m = D x V V = mDmD A metal object has a mass of 25g and a volume of 2.38cm 3. Identify the metal as silver or lead based on its density. Substance Density at 20ºC and 1.0atm (g/cm 3 ) Substance Density at 20ºC and 1.0atm (g/cm 3 ) Helium (gas)0.00001663Zinc (solid)7.13 Oxygen (gas)0.001331Silver (solid)10.50 Water (liquid)1Lead (solid)11.35 Pyrite (solid)5.02Mercury (liquid)13.55 D = 25g 2.38cm 3 D = 10.5g/cm 3 The metal is silver.

18. Density Math Worksheet

19. Density Column Worksheet

20. Density of Liquids Lab

21. The density of a fresh egg is about 1.2 g/mL, and the density of a spoiled egg is about 0.9 g/mL. The density of the egg decreases as it ages because as it spoils, it loses water through the tiny pores in the shell. So, don’t eat an egg that floats! It’s spoiled! Is That a Fact? ! GROSS!!

22. http://www.physics.smu.edu/~scalise/apparatus/triplebeam/ http://learn.uci.edu/oo/getOCWPage.php?course=OC0811004&lesson=006&topic=013&page=13 http://scienceblogs.com/aardvarchaeology/2010/01/golf_ball_autopsy.php http://www.instructables.com/id/LED-Ball/step4/Cut-Ping-Pong-Balls/ http://www.scientificillustrator.com/illustration/bird/feathers.html http://dsc.discovery.com/tv/how-stuff-works/lead.html http://www.honey.com/nhb/features/blog/ http://www.frugallivingnw.com/tips-tricks/75-off-karo-syrup-coupon/ http://www.dawndishsoap.net/ http://www.indyposted.com/9110/chemical-in-plastic-water-bottles-may-pose-health-hazard/ http://www.meijer.com/s/crisco-pure-vegetable-oil-1-bottle-48-oz/_/R-126596 http://en.wikipedia.org/wiki/Rubbing_alcohol http://www.drugstore.com/herbal-essences-body-envy-volumizing-shampoo/qxp189981 http://www.sciencephoto.com/media/102951/enlarge http://www.witchcraftandwitches.com/trials.html Picture Sources