April 27, 2011

April 27, 2011

AttendanceCoke vs. Diet CokeCorrect 12.1A Density Homework (white)Discuss Lab 12AUse water displacement tanks to find volume Learning Targets:

Find volume of an object using water displacement.Apply the formula: D = M/VExamine variations in densities of matter in different

states.

Table of Contents

Date Topic Page

4/7 Matter Web Quest 47

4/8 Particle Theory of Matter 48

4/12 The Atom/MCA Testing 49

4/14 States of Matter 50

4/19 Physical Properties of Matter 51

4/20 Oobleck! 52

4/25 Density 53

4/27 Density (continued) 54

Density (cont) 4/27/11 54

Summary:

Coke vs. Diet CokeHow do you find the density of an object?

What is the formula for density?

How can we find out the volume of the bottles?

How do we find the mass of the bottles?

Density = Mass Volume

What might cause the density of the sodas to be so different ?

Sink or Float?

12.1 Density

1. A solid rubber stopper has a mass of 33.0 grams and a volume of 30.0 cm3. What is the density of the rubber?

Density = Mass Volume

Density = 33.0 30.0

= 1.1 gr/cm3

2. A chunk of paraffin (wax) has a mass of 50.4 grams and a volume of 57.9 cm3. What is the density of

paraffin?

Density = Mass Volume

Density = 50.4 57.9

= 0.87 gr/cm3

3. A marble statue has a mass of 6,200 grams and a volume of 2,296 cm3. What is the density of marble?

Density = Mass Volume

Density = 6,200 2,296

= 2.7 gr/cm3

4a-b.

4.

Full Box = 120.8 kg

Empty = 0.755 kg

120.8 kg - 0.755 kg =

120 kg of plastic

120 kg 0.125 m3

= 960 kg/m3

Type of Plastic = HDPE

b.

HDPE, LDPE, PP, PS

12A Density Lab Discussion

Check your answers. How close are you?

Make changes to your table as needed.

Compare the answer in the “mass” column with your answer. Make changes as needed. You will

also have to recalculate each density.

Compare the density of each material against water = 1 g/cm3.

If the density is greater than water the material should sink.

If the density is less than water the material should float.

Water Displacement

Archimedes was born in Greece in 287 B.C.

12A Density Lab - Challenge

How do you use a displacement tank to measure the volume of a cube?

• Find the volume of each cube by using the water displacement technique.

• Compare your results with those you obtained using the mathematical formula (see Table 2).

• How close are your answers?

•Answer the questions for Challenge 5d on the last page of your lab packet.

Wrap Up

• Summary: You have found volume of objects using two different methods (formula and water displacement). Describe each method. Which technique do you prefer? Why?

• Homework: None Today!

• Flipper: 12A lab goes back to spread #53