Understanding Density

Why does regular A&W soda settle at the bottom and Diet A&W soda stay on top?

OBSERVEWhat do you see?

SHARETalk to a partner

WONDERWhat questions do you

have?

How do you explain the presence of different layers of liquids?

What are the layers? Why are there layers?

Question What would be important to

learn? Questions?

How would you test it?

What did you learn?

Why are there different layers

of liquids?

If you could see the particles inside each layer, how would they

look?

REVIEW: PROPERTIES OF MATTER1. Organize a notebook page2. Copy the table in your notebook. Fill in with the correct answer.

Definition Unit of Measurement

Symbol

Matter

Mass g,kg

Weight N

Volume

3. How do you measure the following: (Explain or provide a diagram) a. mass of a solid, liquid, and solid crystals

b. volume of a liquid, a regular solid, and an irregular solid

1 meter

1 decimeter

1 centimeter 1 millimeterNot drawn to real

size

MEASURING VOLUMEUnit: liters (l) or milliliters (mL)

Liquids

Regular Solids (volume = l x w x h)Irregular Solids (Water displacement)

Measuring Volume of a Liquid

Close Up View of Liquid in Graduated Cylinder

The curved surface of the liquid is called a meniscus. As a standard procedure, always read the level of the liquid at the bottom of the curve

Source: http://www.lincoln.smmusd.org/staff/burdettet_web/meniscus.html

 

Understanding Density

Week of Feb. 27-28

[ ] DAY 1- Introduce

[ ] DAY 2- Explore

Week of March 4-6

[ ] DAY 1- Extend

[ ] DAY 2- Summarize

Why are there different layers of liquids?Possible answers

How would you test it? Explore

Observations What did you learn?

1. Some liquids thicker than others

2. Some liquids are “denser” than others

Density = Mass__ Volume

3.

Why are there different layers of liquids?Possible answers

How would you test it? Explore

Observations What did you learn?

1. Some liquids thicker than others

Mix with water

“Feel the liquid”

Flow Test

K=Javier’s “Fork” test

Drop test

Group 1 2 3 4 5 9Honey Baby oil Alcohol Water Dishwash

ing LMaple syrup

1 0.79

2 0.97

3 0.86

4 1.29

5 0.99

61.4

RANK 6 1 2 4 3 5

Baby oil 0.79

Alcohol0.86

Dishwashing Liquid

0.97

Water 0.99

Maple syrup1.29

Honey 1.4

Why do the liquids in the column separate? Why doesn’t the mass and volume of the liquid matter?

What happens when we drop different objects into the column? • •

Explain why?

Baby oil 0.79

Alcohol0.86

Dishwashing Liquid

0.97

Water 0.99

Maple syrup1.29

Honey 1.4

Full-sized candle floats

Half-sized candle floats

Half-sized candle sinks

A Tale of Three Candles

Explain why?

Mass = 10 g

Vol = 20 mL

Density = Density = Density =

Mass = 10 g

Vol = 20 mL

Mass = 5 g

Vol = 10 mL

Mass = 5 g

Vol = 10 mL

Mass = 2.5 g

Vol = 5 mL

Mass = 2.5 g

Vol = 5 mL

Mass = 2.5 g

Vol = 5 mL

Mass = 2.5 g

Vol = 5 mL

Density = 10g/20mL = 0.5 g/mL

Density = 5g/10mL = 0.5 g/mL

Density = 10g/20mL = 0.5 g/mL

Source: http://www.chemistryland.com/CHM130S/02-MMM/Measure/Measuring.htm

H

L

W

Volume= L x W x H = 10cm x 5cm x 7cm = _________ cm3

Volume = _______ ml

MEASURING VOLUME

Source: http://www.chemistryland.com/CHM130S/02-MMM/Measure/Measuring.htm

How do you measure the volume of an irregular object?

Source: http://www.chemistryland.com

http://www.youtube.com/watch?v=Lwc6QklQGFw

http://www.youtube.com/watch?v=fE2KQzLUVA4 Seven Layer Density

UnderstandingDensity?

D= Mass/Volume

Why are there different layers?

…can explain how to calculate the density of an object.

…can calculate the density of brown sugar in a bag that measures 5cm3 and weighs 500g.

can identify 3 states of matter.

… can explain how to find the volume of an irregular -shaped object.

… can give the units for mass and volume.

…can define density. …can explain how to measure the mass of a solid.

… explain why an ice cube floats in water.

…can calculate the volume of a square wooden box if one side is 6 cm.

… can give the formula for volume.

…can define volume.

…can give the formula to find the density of an object.

…can explain which is heavier: a kg of gold or a kg of feathers.

…can explain how to measure the volume of a liquid.

… can define mass …can explain 2 ways how to change the density of an object