GRAPHING AND VARIABLESX axis—holds the independent

(manipulated) variableY axis—holds the dependent

(responding) variable***DRY MIX***

ACTIVATOR:WORD SPLASH--MEASUREMENTList as many terms or phrases

that we’ve discussed in unit 2 that deal with measurement

DATA TABLES AND VARIABLES

X (INDEPENDENT)

Ex: Volume (mL)

Y (DEPENDENT)

Ex: Mass (grams)

2.0 7.9

3.0 16.2

4.0 25.0

5.0 32.3

SLOPEIs determined by the first and

last data pointsLast y – first y = y2 - y1

last x – first x x2 - x1

Ex: 32.3 – 7.9 = 24.4 = 8.15.0 – 2.0 3.0

DIRECT VS. INDIRECT PROPORTIONS

DIRECT INDIRECT (aka INVERSE)

Shows a positive slope

Shows a negative slope

both factors increase or both factors decrease (do the same thing)

Factors do opposite things

Ex: speed = distance/time density = mass/ volume

Ex: area = length x width

Graph: Graph:

FLIPPED ASSIGNMENT--DENSITY

Visit the following website:http://mswipc.com/problem_sets/density/density_sample_problems.htm

Review all 3 types of density problems posted on this page before class tomorrow.

ACTIVATOR: Explain why these substances are layered?

DENSITY DEMONSTRATIONS: (TEACHERTUBE.COM)

1. The density of liquids2. Underwater volcano3. The density of water is 14. Dr. Reich’s density labhttp://www.teachertube.com/viewVideo.php?video_id=7593

FOR DENSITY LAB:--follow your procedure !!!---DO NOT MOVE CHAIRS AROUND---MUST KEEP GOGGLES ON AT ALL TIMES at

station 2!!!---PART OF YOUR GRADE IS BASED ON

CLEAN UP---WHEN USING SOAP TO WASH CYLINDER,

ONLY USE 1 DROP!---stay with your group and stay quiet!!--- calculate all densities after coming to sit

down

On your data table, add:PART C:Mass of red block=Length =Width=Height=Volume =Density =

DENSITY LAB CONCLUSIONSANSWER 1—5

For #2 you will need these accepted values.

% error = measured – accepted x 100accepted

Water = 1.00 g/mLLiquid A (isopropanol)= 0.786 g/mLLiquid B (glycerin) = 1.26 g/mLSolid sinker (lead alloy) = 11.40 g/ccRed wood (alder) block = 0.4 g/cc

DENSITYDENSITY = MASS

VOLUME**this is a direct proportion**As mass increases, volume increases (or

as mass decreases, volume decreases)Units that measure density:Solids: g/cm3 liquids: g/mL gases: g/L

**see density chart p. 38

Specific gravityThe density of a substance

compared to water’s density (1.0 g/mL)

Float = density less than waterSink = density greater than

water

p. 40 (SHOW WORK AND INCLUDE CORRECT UNIT)

#1. What is the density of a block of marble occupying 310. Cm3 and a mass of 853 grams?

#2. Diamond has a density of 3.26 g/cm3 and a volume of 0.351 cm3. Find the mass.

#3. What is the volume of a sample of mercury having a mass of 76.2 grams and a density of 13.6 g/mL?

ANSWERS1. 2.75 g/cm3

2. 1.14 grams

3. 5.60 mL

4) If a sample of lead is cut inhalf, will its density change?

Explain why or why not.

No b/c mass AND volume both change

by the same factor

5) Find the density in grams/mL of aliquid having a mass of 2 kg and a

volume of 2900 mL.

What might this liquid be?(see p. 38) Would it sink or float in water?

2000 grams / 2900 mL = 0.7 g/mL

It would float because it’s density is less than water’s

SUMMARIZER: DENSITY 3-2-1Name 3 measurements the

density formula involves.Give 2 units that measure

density.Give 1 reason an object may float

in water.

ACTIVATOR: (using your calculator)Calculate the density of a gas

with a mass of 253 grams and a volume of 3.5 L.

SHOW YOUR WORK

ACTIVATOR:Using the Density chart below, name

2 substances that will float in water AND 2 substances that will sink in water.

Brass 8.55Gold 19.3Iron 7.8Uranium 18.7Ice at 0 C 0.92Wood 0.67

Homework

Density handout front 1—13 back ODD****also read LAB carefullyFinish IPAD activity

DENSITY HANDOUT ANSWERS-FRONT SIDE 1. 1.20 g/mL 2. 3.3 g/cc (could be Aluminum which has density of

2.7 g/cc) 3. 700 grams 4. 200 mL 5. 0.757 g/cc 6. 73 mL 7. 1.12 g/mL 8. 290 grams 9. 70 cc 10. 1.53 g/mL 11. 1.8 g/cc 12. 600 grams 13. 1.44 g/mL

BACK---ODD 1--201. 0.23 g/cc3. 0.14 g/cc5. 0.21 g/cc7. 0.27 g/cc9. 0.11 g/cc11. 2.0 g13. 2.7 g15. 2.6 g17. 90. cc19. 41 cc

EXTRA PRACTICE --DENSITY1. 302. 2.03. 24. 3.05..

SUMMARIZER—using the density formula

How is density calculated?

How is mass calculated?

How is volume calculated?

ACTIVATORCalculate the volume of a block

of wood having a denisty of 0.78 g/cm3 and a mass of 300 grams.

WARM UP—DENSITY & GRAPHING 1. Calculate the density of a liquid having a mass of 35 grams and a volume

of 111 mL 2. Calculate the mass of a solid having a density of 2.5 g/cc and a volume of

3 cc. 3. Calculate the volume of a block with a mass of 9.0 grams and a density of

45 g/cm3. 4. Find the density in grams/mL of a liquid having a mass of 3.4 kg and a

volume of 1.0 L. 5. If a sample of gold is cut in half, would its density change. EXPLAIN WHY

OR WHY NOT.

ANSWER THE FOLLOWING QUESTIONS USING THE DATA TABLE BELOW: MASS (g) VOLUME (mL) 3.0 15.0 4.0 10.0 5.0 6.0

6. Calculate slope of the graph’s line. 7. Is this a direct or indirect relationship? 8. What is the responding variable? 9. What is the independent variable?

SUMMARIZERDescribe how the density is

measured for an irregular shaped solid VS. a rectangular shaped solid.

p. 42 #5 p. 54 #1, 2p. 57 #7-10p. 59 # 13b,c 14a,b 17-19,

22a,b 32b, 33b

ACTIVATORPut the object’s in the lab in order of

least to greatest density:

Water = 1.00 g/mLLiquid A (isopropanol)= 0.786 g/mLLiquid B (glycerin) = 1.26 g/mLSolid sinker (lead alloy) = 11.40 g/ccRed wood (alder) block = 0.4 g/cc

Which ones would sink in water? Which ones would float in water?

QUIZ-- DENSITY= mass/volume

REMEMBER SIG FIGS AND UNITS!!SHOW WORK!!1. Calculate the density of a solid having

a mass of 45 grams, a length of 2 cm, a width of 3 cm, and a height of 1 cm.

2. An object’s density is 3.6 g/cc. It is put into a graduated cylinder initially having 25.0 mL. The water level rises to 25.2 mL. What is the object’s mass?

3. Find the volume of an object with a mass of 25 kg and a density of 5 g/mL.