Properties of Water Lesson 1

TESLA Water 2011

The Big Idea of this Investigation

Water, which covers most of Earth's surface is the only substance on Earth that is found naturally in all three states of matter. Water can change from one state to another depending on the amount of heat that is added or taken away from it.

ENGAGING SCENARIO

The Aquatic Center is going to invite classes to visit their facility and they would like the field trips to be fun for the students. They are planning on setting up some activities for students to learn something about water and they need your help. They would like for us to try out some of the activities they are planning to see if the activities will help students learn something about water. They have sent us some materials and printed information that may help us. They also need us to keep accurate records and labeled drawings in our science notebooks. We have been asked to send them a report in a couple of weeks. They want us to share what we learned so they will know whether to use the activity with students.

• •

What is the problem we need to solve? What do we need to investigate?

Kit Inventory

These are the objects that have been sent to us by the Aquatic Center. I have put them in this large bag. Let’s see if we can identify them.

• What color/shape is the object?

• Where have you seen this object before?

• What do you think we will use this for in the unit?

New Vocabulary

Here is a cup of

water

. It is an earth material. An

earth material

is a substance that makes up or comes from the earth. A

property

is a characteristic of a material, something you can observe, such as shape, color, temperature, and smell.

Assessing our Prior Knowledge

•What do we already know about water? •What does it do? •How is it used? •Where is it found?

One of the activities that the Aquatic Center wants to try out has something to do with water when it spills on different surfaces. -What happens when water spills or gets dropped on something? -Does water do the same thing when it lands on all surfaces?

Focus Question

(What is the problem?) What happens when water spills or is dropped on different surfaces?

NOTEBOOK ENTRY

These are the materials that the Aquatic Center has sent us to help us find out what happens when water spills on different surfaces. sheets of waxed paper paper towels plastic dropper.

aluminum foil plain paper

Prediction

(related to the focus question) I think that when water is spilled or dropped on ________ it will ___________________________________ because ________________________________________ NOTEBOOK ENTRY

When you place individual drops of water on the different surfaces, I need you to observe and describe what you see. Be sure to observe the drops of water from all angles and to pay attention to the shape that the water makes. Scientists always try to make careful observations.

Surface Tested: ______________ Top View Side View

NOTEBOOK ENTRY

Solving our Problem

Now we are going to investigate what happens to drops of water when placed on different surfaces.

Here is the plastic dropper. I am going to demonstrate how to use the dropper to make all our drops fair and equal in size.

① ② ③ ④ ⑤ Squeeze the bulb.

Put the tip in the water.

Release the pressure on the bulb.

Take the dropper out of the water.

Squeeze the bulb gently to release one drop

Why would a scientist want to use fair and equal sized drops?

Making Meaning Conference

What happened to the drops of water on the waxed paper surface?

What happened to the drops of water on the foil surface?

What happened to the drops of water on the paper towel surface?

What happened to the drops of water on the plain paper surface?

New Vocabulary

Absorbs :

When a liquid soaks into a surface

Beads:

When a liquid sits on top of a surface

Claims and Evidence

Use your own words, or words from the word wall, to help you complete the following sentences in your science notebook.

I claim that water _______when it is dripped on ______. I know this because… I also claim that water ________ when it is dripped on ___.

I know this because…

NOTEBOOK ENTRY

Reflection/Conclusion

Revisit your original prediction… Explain how the evidence did or did not support your original prediction?

My prediction was accurate or was not accurate I wish to revise my prediction because… because…..

What did you learn…?

What really surprised you…?

What new questions do you have…?

What would you like to know more about…?

NOTEBOOK ENTRY

Part II: Properties of Water

The Aquatic Center is very pleased with what you have learned about water absorbing and beading on different surfaces. Today they have a new problem they would like us to solve. This problem is also part of the activities they have planned for their field trips. They are trying to figure out how many drops of water can fit on a penny.

• •

What is the problem we need to solve? What do we need to investigate?

Focus Question

(What is the problem?)

How many drops of water can fit on a penny?

Previous Knowledge

Share experiences with water that may help you make a prediction.

Prediction

(related to the focus question) Prediction:

I think that ________ drops of water will fit on a penny because _____________________________________.

NOTEBOOK ENTRY

Collecting Data

Procedure:

1.

2.

3.

4.

Place a dry penny on a paper towel.

Use a dropper to place drops of water on a penny one at a time.

Hold the dropper straight up and down and release drops from about 1cm above the penny.

Count the number of drops as you go until the water spills over the top of the penny.

______

Penny (Side View)

Descript ion: Trial # 1 Trial # 2 Trial # 3

NOTEBOOK ENTRY

Making Meaning

What shape was the surface of the water on the penny before it spilled?

New Vocabulary

Dome:

The water surface curves up above the penny to form a dome

Surface Tension:

A property of water that caused water to “stick” together and form a ball or dome

The people from the aquatic center are also curious to know what would happen if soapy water were added to the water dome.

Prediction

(related to the focus question) Prediction:

I think that adding soapy water

will or will not

change the number of drops of water that will fit on a penny because…

NOTEBOOK ENTRY

Collecting Data

Procedure:

1. Set up as before with a dry penny on a paper towel.

2. Add drops of plain water on a penny to make a dome.

3. While observing the dome from the side view, add one drop of soapy water to the dome.

4. Count the number of additional drops of soapy water needed to spill the dome.

# of Drops of Soapy Water that can be added to a penny

______

Penny (Side View) Trial # 1 Trial # 2 Trial # 3 Description:

NOTEBOOK ENTRY

Making Meaning

How does soap affect surface tension? What was your evidence?

If soapy water can affect surface tension, how do you think salt might affect the number of drops that will fit on a penny?

Prediction

(related to the focus question) Prediction:

I think that adding salt water

will or will not

change the number of drops of water that will fit on a penny because…

NOTEBOOK ENTRY

Collecting Data

Procedure:

1. Set up as before with a dry penny on a paper towel.

2. Put 15 drops of plain water on a penny to make a dome.

3. While observing the dome from the side view, add one drop of salt water to the dome.

4. Count the number of additional drops of salt water needed to spill the dome.

# of Drops of Salt Water that can be added to a Penny

Trial # 1

______

Trial # 2

Penny (Side View)

Trial # 3 Description:

NOTEBOOK ENTRY

Making Meaning

How does salt affect surface tension?

What is your evidence?

What shape does water make on a flat surface?

What shape does water make when falling from a dropper?

What causes water to form a dome on flat surfaces and a ball when falling?

How did you change the surface tension of plain water?

Surface Tension

Water Bead or Dome H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H Penny H O H Water Molecule Water molecules are too small for us to see with our eyes alone, but they are composed of one Oxygen (O) atom and two Hydrogen (H) atoms. This is why water is commonly called H 2 O.

Have you heard the saying opposites attract?

In a way the atoms that make up a water molecule are kind of like magnets. The hydrogen atoms are positively charged and the oxygen atoms are negatively charged so the water molecules are attracted to each other. This attraction causes the molecules to want to “stick” together and form a dome on a waterproof surface.

H O H - H O H + Attraction

Surface Tension

Soapy Water Plain Water H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H H H O H H O H H O H H O O H H H H O O H H O H Penny Penny Soap Molecule In our new model, the blue rectangle represents a soap molecule. Soap molecules act as a “barrier.” When soap is present in the water, the water molecules have a harder time attracting each other so surface tension is reduced. As a result, fewer water molecules will fit on the same penny.

Claims and Evidence

Use your own words, or words from the word wall, to help you complete the following sentences in your science notebook.

Preparing the Investigation

I claim that surface tension is a property that causes water to _______________________.

I also claim that the surface tension of water can be changed by _____________________.

I know this because …

NOTEBOOK ENTRY

Reflection/Conclusion

Revisit your original prediction… Explain how the evidence did or did not support your original prediction?

My prediction was accurate or was not accurate I wish to revise my prediction because… because…..

What did you learn…?

What really surprised you…?

What new questions do you have…?

What would you like to know more about…?

NOTEBOOK ENTRY

Part III: Properties of Water

Because of your hard work, The Aquatic Center now has two activities set up for field trips. They found your recent information about the property of surface tension very interesting. They have one more activity planned for the properties of water and need your help to see if it will help students learn more about the properties of water. They would like students to know what happens to a raindrop that falls into a stream flowing down a mountainside. What do you think happens to the raindrop? .

• •

What is the problem we need to solve? What do we need to investigate?

New Vocabulary

The aquatic center wants us to prove what happens to drops of water when they are placed on a

slope

or slanted surface.

Focus Question

(What is the problem?)

How can we prove the direction water flows when placed on a slope?

NOTEBOOK ENTRY

Prediction

(related to the focus question) Prediction:

I think that when water is placed on a slope it will _________.

I think this because _________________________________.

NOTEBOOK ENTRY

Collecting Data

Procedure:

1.

2.

3.

4.

5.

Create a slope by propping one end of a tray on a book.

Lay waxed paper on the tray to create a smooth surface.

Use droppers to drop water on the waxed paper.

Observe and record what happens in your science notebooks.

Return the water to the plastic cup when it collects at the bottom of the tray.

Making Meaning

• Which direction does the water flow when placed on a slope?

• If you raced different sized water domes, which one would get to the bottom of the slope first?

• What happens to the water domes when the steepness of the slope is increased?

NOTEBOOK ENTRY

Claims and Evidence

Use your own words, or words from the word wall, to help you complete the following sentences in your science notebook.

the Investigation

I claim that water flows _____________ a slope. I know this because… I claim that bigger domes of water flow __________ than smaller domes of water. I know this because… I also claim that water flows ___________ down a steeper slope. I know this because…

NOTEBOOK ENTRY

Reflection/Conclusion

Revisit your original prediction… Explain how the evidence did or did not support your original prediction?

My prediction was accurate or was not accurate I wish to revise my prediction because… because…..

What did you learn…?

What really surprised you…?

What new questions do you have…?

What would you like to know more about…?

NOTEBOOK ENTRY