An interactive presentation by Marcy Bradshaw Heres a

An interactive presentation by Marcy Bradshaw

Here’s a riddle for you. . . Name something that keeps going around, is invisible, is fun to play in, and keeps you alive?

Give up? What? ? ? You can’t give up! Try Again! Okay, the answer is. . . (Click the mouse) Water !

The Water Cycle An interactive presentation by Marcy Bradshaw We Will Find Out: 1. How Water Changes Form 2. How Water Moves From Place to Place.

This lesson is linked to the Utah State Core Curriculum. • Click here to see the Science Core for Davis County.

Vocabulary you will learn: • • • Evaporation Condensation Precipitation Percolation Run Off Water Cycle Write these words in your journal, and add the definitions as you learn them.

How Water Changes • Water is the only material on Earth that has three forms in nature. • On your paper: Name three forms that water takes, and write an example of where you might find each form.

Here are some hints…. . 1. . . • Is water ever “hard, ” like a piece of glass? • We call this form a “solid. ”

2. . • Is water ever runny, like when you drink it? • We call this form a “liquid. ”

3. . • Can water float in the air? • We call this form “water vapor. ”

Now. . . • Talk with your group about examples of the three forms of water.

The form that water takes depends upon the amount of heat (or thermal energy) in it.

When water is heated…. • Liquid water is changed into a gas that spreads out into the air. • Evaporation is the changing of a liquid into a gas. • Evaporation changes liquid water into an invisible gas – water vapor.

When water vapor is cooled and comes in contact with something solid…. . • Condensation takes place.

• Condensation is when water vapor (a gas) changes into a liquid • . . . like tiny drops of water on the outside of your cold glass of pop.

After water becomes vapor, it cools to form water again. The water returns to the Earth as Precipitation

Precipitation is water that falls to Earth as: Rain, Snow, Sleet, or Hail.

The same water on Earth goes through the water cycle over and over again! • The water you use to brush your teeth is billions and billions of years old!

The movement of water from Earth’s surface into the air and back to Earth again is called. . . “The Water Cycle”

Now let’s review… • 1. What is the water cycle? • The movement Discuss this with your group and click when you think you have the answer. . . of water from Earth’s surface into the air and back to the surface again.

2. What three forms can water take? Click when you have the answers.

Water’s three forms are: • Liquid • Solid • Gas (Water Vapor)

3. What is Evaporation? Give an example. • The changing of a liquid into a gas. Examples: • Steam from a pot of boiling water. • Water vapor rising into the sky from a lake or ocean. • A shallow pan of water sitting in the sun is empty the next day.

4. What is Condensation? • Water vapor (a gas) changes back into a liquid…(little drops). • This happens when the water vapor is cooled and finds something solid to stick onto.

Okay…once more now…. What two conditions must be present before condensation can take place? • The water vapor must hit something solid • And the solid surface must be cooler than the water vapor.

5. Predict what you think “Run Off” means.

“Run Off” • When the soil cannot absorb any more moisture, the rain water “runs off” the surface of the earth - downhill to eventually collect into a small stream, then a river, then back to a lake or an ocean.

Now try this quiz… • A. Evaporation changes water from a _____ into a _____. • B. Condensation changes water vapor into a ____. • C. What is the water cycle? Click here to review this information.

Here are your answers: • A. Evaporation changes water from a liquid into a gas. • B. Condensation changes water vapor into a liquid again (tiny drops of liquid). • C. What is the water cycle? The movement of water from one form to another all over the earth. Click here to go on…

Critical thinking… • What would happen if water could evaporate but could not condense? Discuss your answer with your group.

How does water on land return to Earth’s oceans in the water cycle? Choose one answer and discuss it with your group: A. B. C. D. By evaporating By turning to ice By run off (the flow of rivers) By entering plants

Answer: D – Run Off Click here for an extra-credit question about your health.

Health Link: 1. What is that liquid that forms on your skin when you exercise for a long time? 2. What happens to that sweat? How does your skin dry off? 3. What happens to the temperature of your skin when your sweat evaporates? Click here for answers:

Health Link Answers: 1. When small droplets of water form on your skin after exercising, we call this “sweat. ” Your skin produces this salty water in other situations also, not just after exercise. Can you think of other times that you sweat? 2. After you stop exercising, the small droplets of sweat evaporate. 3. Evaporation of the sweat droplets helps to cool the temperature of your skin. Click on button to return to slide show……….

Math Link For extra credit, try a related math problem. Write the answer in your journal. Click on the book to go to the math problem.

What is Percolation? When the rain, sleet, snow, or hail falls on the ground, some of it usually “seeps” (or percolates) into the earth. This water continues to percolate deeper and deeper into the earth, until it eventually hits bedrock or collects in underground “rivers. ” The rivers eventually make their way to the oceans or lakes, to be collected in the water cycle again.

Writing Link Find pictures in magazines that show the parts of the water cycle. Mount them on a poster board. For each picture, write a sentence that tells what is happening. Share your work with the class.

Transpiration • …is the loss of water to the air through plant leaves. In some places its effects are minimal. In other places, such as tropical rain forests, transpiration is so great that it can affect weather. • Click here for an experiment to see how plants give off water.

A Transpiration Challenge…. • Cover a houseplant’s leaves completely with a clear plastic bag. Tie off the bag at the base of the stem. The bag should not cover the plant’s pot. Place the pot on a shallow dish and water the plant’s soil until moist. (click and keep going…)

Scientists who conduct experiments usually use a “control”…. • Take a similar bag, and pull it through the air to fill it with air. (Do not blow into the bag. Can you guess why? ) Tie off this bag, and use it as a control. • Put the plant and the air-filled bag in a warm, sunny place. • What do you predict will happen in the bag that is attached to the plant?

After some time, the bag over the plant will contain a significant amount of water. Where do you think this water came from? Click here for the answer.

The water in the bag was given off by the plant’s leaves. This is called transpiration.

• Now you know all about the Water Cycle! Click here to play some fun games with water. You will go to the “Project Wet” website. Press the “back” key when you are finished with the water games. Click this button to end the show…. .

Davis District Core Curriculum 4 th Grade – Science • Core Standards of the Course Standard 1 • Science Benchmark Matter on Earth cycles from one form to another. The cycling of matter on Earth requires energy. The cycling of water is an example of this process. The sun is the source of energy for the water cycle. Water changes state as it cycles between the atmosphere, land, and bodies of water on Earth.

Davis District Core Curriculum 4 th Grade – Science, Continued • Students will understand that water changes state as it moves through the water cycle. • Objective 1 Describe the relationship between heat energy, evaporation and condensation of water on Earth.

Davis District Core Curriculum 4 th Grade – Science, Continued a. Identify the relative amount and kind of water found in various locations on Earth (e. g. , oceans have most of the water, glaciers and snowfields contain most fresh water). b. Identify the sun as the source of energy that evaporates water from the surface of Earth.

Davis District Core Curriculum 4 th Grade – Science, Continued a. Compare the processes of evaporation and condensation of water. b. Investigate and record temperature data to show the effects of heat energy on changing the states of water. •

Davis District Core Curriculum 4 th Grade Science, Continued • Objective 2 Describe the water cycle. a. Locate examples of evaporation and condensation in the water cycle (e. g. , water evaporates when heated and clouds or dew forms when vapor is cooled).

Davis District Core Curriculum 4 th Grade Science, Continued a. Describe the processes of evaporation, condensation, and precipitation as they relate to the water cycle. b. Identify locations that hold water as it passes through the water cycle (e. g. , oceans, atmosphere, fresh surface water, snow, ice, and ground water). c. Construct a model or diagram to show water continuously moves through the water cycle over time.

Davis District Core Curriculum 4 th Grade Science, Continued a. Describe how the water cycle relates to the water supply in your community. • Skills and Strategies 1. Science language students should use: vapor, precipitation, evaporation, clouds, dew, condensation, temperature, water cycle

Now you know what is in the Davis School District Curriculum about the Water Cycle… Click on the lightbulb to return to the slide show.

The End

Math Link Suppose that 100 liters of water evaporate from a lake; 50 liters fall back on the lake as rain, 10 liters turn to ice on a mountain. The rest of the water flows back to the lake from a river. How much of the 100 liters does the river carry?

Answer to math link: 40 liters. No water is lost in the water cycle, so the amount coming back must be the same as the amount that went out. Click on the picture to go back to the show…