What do you notice in this picture?

Why do you think this man is floating so high

in the water?

Physical Properties of Matter

DensityConductivityMagnetismMelting Point/Boiling PointSolubility

Today’s FOCUS

By the end of class, we will be able to…

Calculate/determine the densities of various materials.

Analyze the densities of various materials using data.Explain that these properties are independent of the amount of the sample.

What is density?

Density is a physical property of matter that relates to both mass and volume. how much mass (stuff) is packed into a

certain volume (space).Density is not dependent on the amount of the

sample. Density is the amount of mass per given volume

so it is measured in g/mL or g/cm3. The formula for density is mass ÷ volume.

Note to self: Density of Water is 1g/mL

Which one is more dense?

How about this: Which square has the most people packed into it?

Keep in mind that both

squares are the same

size. So they can both hold

the same amount of people.

Demonstration: People in a square

Which one is more dense?

Compare this slide to the last one. What’s the difference between the squares?

These two squares have

the same amount of

people with a different

amount of volume

(space).

Density at a glance…

On the left side of your journals, list the liquids from most dense to the least dense. Explain why in at least one complete sentence.

Understand that…

Objects that are less dense than the liquid they are in float.

Objects that are more dense than the liquid they are in sink.

What can you say about the liquid in this picture compared

to the man?

Which of these substances will float or sink in water?

Substance Density (g/mL)Platinum 21.4Aluminum 2.7Air 0.00129Gasoline 0.70Silver 10.5Olive oil 0.89Ice (0 oC) 0.92Iron 7.8Nickel 8.8Gold 19.3

A closer look at density

Density = mass OR mass ÷ volume.

volume

Units for density: g or g .

cm3 mL

Why are these the units for density?

ALWAYS REMEMBER

UNITS!

How do we find mass?

Mass is the amount of matter in an object.

mass is measured in grams (g), kilogram (kg)

Mass can be found using lab equipment:Digital Scale Triple beam balance

Triple Beam Balance

Digital S

cale

How do we find volume?

Volume is the amount of space taken up.

Volume is measured in milliliters (mL), cubic centimeters (cm3)

Volume can be found using Metric ruler Graduated cylinder

When measuring volume…

Regular objects (cubes, rectangles), a metric ruler can be used to measure L x W x H

Irregular objects (rocks, marbles, etc), a graduated cylinder is used to measure the amount of water that is displaced.

Initial water level

Final water level

Determine the volume of the pebbles in the picture.

Whole Group Exploration (GIZMOs): Density Laboratory (Right Side)

Whole Group Exploration (GIZMOs): Density Laboratory (Right Side)

Left Side

Remember!

Density = mass OR mass ÷ volume.

volume

Units for density: g or g .

cm3 mL

ALWAYS REMEMBER

UNITS!

Calculate the Density of each object in the last column (Right Side)

Left Side

Let’s try a density problem together

Frank has a paper clip. It has a mass of 9g and a volume of 3cm3. What is its density?

Frank also has an eraser. It has a mass of 3g, and a volume of 1cm3. What is its density?

Does density depend on the amount of a sample? Let’s explore…

What’s the difference between the substance you see in the pictures? On the left side of your

journal:1-Describe how the substance is behaving in all the pictures. 2-Estimate how much of the substance you see in all of the pictures. 3-Does the amount change how the substance behaves? 4-What do all pictures have in common no matter what? Keep behavior of the substance in mind when answering…