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Matter - Air

A unit with lesson plans, activities, & lab notes for the middle grades

Questioning is the beginning of all learning.

Introduction

This plan investigates air and its properties as one state of matter. Properties of how it takes up space, has volume, exerts pressure, and flows through space.

It is one unit from of a sequence of units that investigate matter to review and develop a deeper understanding of the properties of its states, as a solid liquid, and air/gases.

Includes detailed plans, suggestions, solutions, worksheets, or lab notes, with a material list of items easy to obtain from home or thrift stores.

Related activities

  • Matter - solid liquid, & air/gas
  • Air
  • Bubbles
  • Liquid - water
  • Pressure
  • Heat energy activities
    • Heat energy hot cold - teacher directed plan with lab notes to explore: hot & cold with touch, variety of activities using water, mixing hot & cold water, warming ice water to boiling, salt & ice, temperatures of cars in sunshine, blowing hot & cold bubbles, conduction, convection, & radiation.
    • Heat energy and conservation - candle and heat
  • Plasma

Planning information

Learner background information

A plan designed for learners who have prior knowledge in cause and effect. The use of observations to make inferences, models as explanations for observable and non observable events, change, relative position, and working in groups is helpful, but not necessary. Basic understanding of solid, liquid, and gas as in (matter unit) is helpful.

Instructional planning

Intended learnings & learner's thinkings

Content Big ideas, concept & facts, & outcomes
(Source concepts & misconceptions)

Big ideas and specific outcomes:

We understand our world and make decisions based on our understanding of the physical matter in it, the properties they have and how winteract with outher matter, and how we can use them to make our lives better.

Concepts and facts

  • Matter:
  • Properties
  • Equilibrium
    • When objects exert equal forces on each other they are at equilibrium.
    • When objects are not in equilibrium one will displace the other.

Outcome

Explain how air exerts pressure and will flow to spaces with less pressure.

Science concepts: physical, earth, life

Big ideas: Matter takes up space and has mass.

Related concepts

  • Air is matter; occupies space, exerts a force or pressure.
  • Matter occupies space.
  • States of matter include gas, liquid, solids.
  • No two objects can occupy the same space at the same time.
  • Gases and liquids flow when they exert unequal pressure on each other.
  • Air can be pushed out of the way by solid objects, liquids and gases.
  • There is a lot of air above us pushing down.
  • Solids, liquids, and gases exert more pressure at the bottom than at the top.

Outcome

  • Use accurate verifiable information to consider properties of gases and how understanding them can influence us in making decisions.
  • Describe air as a gas that is matter that takes up space and has mass. It exerts a force and flows when not at equilibrium.

Anticipated learner thinkings & misconceptions

Misconceptions for matter

Scoring guides suggestions (rubric)

Air as matter (scoring guide)

Top level

  • Air is matter, takes up space, has mass, and will flow from higher pressure areas to lower pressure.
  • Air moves water.
  • Can feel air when the wind blows or a person exhales.

Lower level

See Scoring Guide for the Inverted Jar With Holes Investigation extensive list of learner responses for different levels of understanding how water does and does not enter the jar.

Inquiry, process, & cross cutting concepts & skills

Inquiry (How science inquires for understanding: process, skill, methodology, practice)

When I experiment I collect observations of properties to describe different objects and can use those properties to describe change (whem properties change they become variables) when objects and systems interact. This helps me make claims to explain what is happening, and make models to predict what might happen in the future.

Related concepts and facts

Properties of objects are determined by the elements from which they are made. Properties can remain constant, change, and be measured. They are used to identify objects, as variables in experiments, operational definitions, and explanations. Properties of matter include: color, texture, size, shape, mass, volume, density, temperature, chemical, energy, states of matter (solid, liquid, gas, plasma) and the ability to interact with other objects. Properties can be measured with scientific tools and compared to a standard unit (linear, time, temperature, mass, volume, and density)

  • Observed changes can be described as changes of properties (variables).
  • Variables are observations of a property that changes - size, shape, temperature, amount, volume, rate, ...
  • When people disagree on an observation, they usually make more and better observations.
  • Observation, creativity, and logical argument are used to explain how variable changes effect resulting observations.
  • Observed changes can be explained as being caused by changes of variables (changes of properties/ characteristics).
  • Explanations are based on observations.
  • Evidence is observation.
  • Inference is an explanation based on observation.
  • When people disagree on explanations, they can make more observations or change their explanation.
  • Better decisions are made when information is verified before being considered accurate and used to reason and develop explanations and models to understand the world and make decisions.
  • People make better decision when they understand and consider the positive and negative influences that effect their decision making.

Outcome

Describe change as a result of interactions. Describe those interactions as changes of a characteristic/ property (variable) that interacts with the object that changes (model).

Specific outcomes -

  1. Describe properties of air and use them to explain and model how air interacts with air and other objects.

Cross cutting

Systems, Order, & Organization; Evidence, Models, and Explanations; Constancy, Change, and Measurement; Evolution and Equilibrium; Form and Function

See more proceess concepts & misconceptions

Related concepts and facts

  • Observational data and reasoning is used to explain interactions. Evidence is something that is observed and can be used to understand what is happening and make predictions about future changes.
  • Explanations are based on observation derived from experience or experimentation and are understandable.
  • Pictures or symbols can represent objects.

 

Model

  • Models are structures that correspond to real objects, events, or classes of events that have explanatory and predictive power (physical objects, plans, mental constructs, mathematical equations, computer simulations...) that may or may not be observed with real objects, systems, and events. 
  • Model is an explanation based on observations, facts, laws, inferences, thought, and reasoning. 
  • Models represent systems or things used as an example to follow or imitate to provide an explanation.
  • Models can be used to think about events or processes that happen very slow, fast, or on a too small or large scale to change easily or safely. 
  • Mathematical models can be displayed on computers and changed to see what happens. 
  • Models are used to represent things in all dimensions of science physical, earth, and life science.
  • Models are created with similar processes, which can be an algorithm or procedure. Such as in the diagram.
  • Model of models 
  • A model, though different from the real thing, can be used to learn something about the real thing.
  • Seeing how a model changes may suggest how the real thing works if the same were done to it. 
  • Models make predictions. 
  • More than one model can represent the same thing or event. 
  • The kind of model and its complexity depend on the purpose of using the model. 
  • Models are never exact representations.
  • A model that is too limited or complicated may not be useful. 
  • A model represents entities and the relationships between them.
  • There are two basic types of models, physical and conceptual. Conceptual communicate through words and drawings, or can be physical and demonstrable. 
  • Models help generate ideas, solve problems, make predictions, help think. 
  • Models can be used to represent new ideas and inventions.

Outcome -

  • Make observations of change, identify variables associated with the change, and create explanations and models of how the variables effect those changes.

Specific outcomes -

  • Identify properties that change.
  • Relate variables to change with an explanation.
  • Generalize explanations of how properties change as models to explain future situations.

Perspectives

Engineering & Technology

  • People have always had problems and invented tools and techniques (ways of doing something) for scientific inquiry and technological design. 
  • The two have similarities and differences. 
  • Scientists propose explanations for questions about the natural world, and engineers propose solutions relating to human problems, needs, and aspirations. 
  • Technologies exist within nature and so they cannot contravene physical or biological principles. Technological solutions and technologies they have side effects, costs, carry risks, and provide benefits. 
  • Many different people in different cultures have made and continue to make contributions to science and technology.
  • Technology is essential to science, because it provides instruments and techniques that enable observations of objects and phenomena that are other wise unobservable due to factors such as quantity, distance, location, size, and speed.
  • Technology provides tools for investigations, inquiry, and analysis. 
  • Science and technology are reciprocal. 
  • Science helps drive technology, as it addresses questions that demand more sophisticated instruments and provides ideas for better instrumentation and technique. Technological designs have constraints that engineers, architects, and others must take into account to solve practical problems.
  • Some constraints are unavoidable, for example, properties of materials, or effects of weather and friction; other constraints limit choices in the design, for example, environmental protection, human safety, and aesthetics. 
  • The knowledge base for science is recorded in print and electronic media and can be found and understood by people in and out of classrooms

Personal and Social Science

  • The application and the use of models in science and technology can and will benefit society.
  • Model helps me internalizing or abstracting understanding.

Nature of Science

  • Science can provide ideas for our protection and desire for a better life.
  • Scientists use models.

History of science

See also Concepts & misconceptions also science, math, technology timeline

  • People have practiced science and technology for a long time.
  • Science develops over time.
  • Science investigators such as

Strategies and activities to achieve intended learnings

Are designed based on the learning cycle theory & method

Pedagogical Overview

Activities Sequence to provide sufficient opportunities for learners to achieve the targeted outcomes.

Make sure learners have the prior knowledge identified in the background information.

  1. Balloons and water
  2. Inverted cup pushed under water with and without paper towel
  3. Jars with 2 holes in lids investigate how water does an does not flow through the hole(s).
  4. Plastic cup filled with water and holes punched through the side at the top, middle, and bottom
  5. Remove water from a jar without lifting it from the water Use a plastic tube, syringe to remove a cup filled with water and submerged.
  6. Breaking a stick with air pressure break a stick on a table with one-third of it hanging over, one full newspaper sheet placed on top of the other two-thirds, karate chop
  7. Straw with water and finger on top
  8. Cup filled with water with card board over top and inverted
  9. Challenge: How can air lift a person?
  10. Crushing a can
  11. Looking inside a balloon

Focus question

Unit focus question:

What is air? How do we use it and respect it?

Sub focus questions:

  1. What is matter?
  2. What is air?
  3. What are the properties of air?
  4. Is air matter?
  5. What causes air to flow?
  6. What is air pressure?

Materials

  1. Balloons inflated to different sizes (at least three), science journal or drawing materials,
  2. Clear glass shaped container, tub of water, paper towels
  3. Baby food jar, several lids for each jar, one with no holes, one with one hole in center, one with two holes - one toward each opposite edge, tub of water
  4. Large plastic pop cup, punch one hole at the top, middle, and bottom of a side, cover each hole with masking tape, fill with water, hold over bucket, pull tape from the holes, lab notes & drawing supplies
  5. Baby food jar, plastic tubing, syringe that the tubing will fit, tub of water
  6. Cheap yard stick, full sheet of newspaper
  7. Straw, cup of water
  8. Cup, index card, or oak tag, large enough to cover the opening on the cup, water, and tub of water
  9. Plastic bag, air pump, duct tape, board, chair, person
  10. Hot water, can with screw on lid, ice

Resources and Materials

Lab notes

  1. lab note 1 - Balloons and water
  2. lab note 2 - Inverted cup without & with paper towel under water
  3. lab note 3 - Jars with 2 holes in lids
  4. lab note 4 - Plastic cup with three holes punched in the side
  5. lab note 5 - Remove water from a jar without lifting it from the water
  6. lab note 6 - Breaking a stick with air pressure
  7. lab note 7 - Straw with water & finger on top
  8. lab note 8 - Upside down cup of water
  9. lab note 9 - Challenge: How can air lift a person?
  10. lab note 10 - Crushing a can with air
  11. lan note 11 - Looking inside a balloon

Lesson Plans

Activity 1 - Balloons and water

Materials

  • Balloons inflated to different sizes (at least three), tub of water, science journal or drawing materials

Focus questions :

  1. What is inside a balloon?
  2. What happens when balloons are put into water?

Learning outcomes:

  1. Explain how the air takes up pace in the balloon and together they push the water aside. Both can not occupy the same space at the same time.
  2. Give examples of how air takes up space.

Suggested procedures overview :

  1. Put different sizes of balloons under water.
  2. Observe how the water moves.
  3. Draw and explain how the balloon pushes the water aside and will change the level of the water in containers.
  4. Describe a general explanatin as amodel.

Exploration

Activity:

  1. Put learners into groups or have learners take turns to demonstrate the investigation.
  2. Blow up a balloon and tie it off.
  3. Ask. What is inside this balloon?
  4. Ask. What will happen when the balloon is pushed into the water.
  5. Listen to responses and do not comment on accuracy.
  6. Ask. What will happen if balloons of different sizes are submerged in water?
  7. Ask. How they can record the data. Can draw pictures of the different sizes of balloons and the different levels of water.
  8. Have learners submerge balloons and record data.
  9. Have learners share their pictures.
  10. Have them pick one of their pictures and line them up according to the results.

Invention

Activity:

  1. Ask. What can we learn from the results?
  2. What does the air in the balloon do? The air takes up pace in the balloon.
  3. Whatdo our pictures show that happens to the water when the balloon is put in? It is pushed aside.
  4. Why? Together they push the water aside. Both can not occupy the same space at the same time.
  5. Ask. How can we make a general statement about air? Air takes up space and it can push and move other objects. The push is the pressure it exerts.
  6. Review or introduce what a model is.
  7. Ask if their gernal statemnt is a model? Yes
  8. Give examples of how air takes up space. Air moving a curtain beside an open window. Air blowing from furnace or air conditioner pushes ...
  9. Ask where at home would they be able to see the same kind of results Putting dishes into a kitchen sink, getting into a bath ….
  10. Ask. How they can you use your model to explain motion and interactions.

Activity 2 - Inverted cup without & with paper towel pushed under water

Paper towel and baby food jar

Materials :

  • Clear glass shaped container, tub of water, paper towels, journal or drawing materials

Focus questions :

  1. What happens to an empty glass when it is put into water?
  2. How can you put a paper towel under water and keep it dry?

Learning outcomes:

  1. Explain how air in a glass will and will not flow from a glass in water.

Suggested procedures overview :

  1. Put a cup under water and see how it flows into the cup.
  2. Push an inverted cup under water and see how the water will not flow into the cup.
  3. Push an inverted cup, with a paper towel, under water and show how the water will not flow into the cup and the paper towel will remain dry.

Scoring guide for

Top level

  • Explain that air fills the space in the cup and the water will not flow in, unless it can push the air out.

Lower level

Exploration

Activity:

  1. Put learners into groups.
  2. Ask. What will happens when a cup is placed in water? Accept all answers. Depends on how it is placed, but usually water will flow into it.
  3. Ask. What will happen if the cup is pushed open end down into the water? Accept all answers.
  4. Tell. Take these cups and insert them into the water like ... open side first.
  5. Learners do the activity and draw where the water is.

Invention

  1. Share their drawings and discuss where the water goes. The air in the glass pushes the water in the tub higher.
  2. Ask. Where the water is when the glass is tipped to the side? The water will not go into the glass, unless air escapes. Proof see air bubbles.
  3. Have them draw pictures to show their answers, discuss, and have them prove their explanations.
  4. Ask. What would scientist call your drawings and eplanations? models

Discovery

  1. Suggest they can use what they learned to make a magic trick and amaze people who don't know about air. Those people and young people will think water will go in the glass so if you put apaper towel inside, they will think it will get wet.
  2. Or Ask. How can they could use the paper towel to prove that there was or was not water in the glass when it was pushed under the water? Crumpel the towel and insert it into the glass, then put the glass open end straight down into the tub of water. Hold for awhile, remove, and amaze the crowd by pulling out a completely dry paper towel.
  3. Ask. What do you thin will happen if the cup is placed open end down into the water with the paper towel inside? The towel won't get wet.
  4. Have them do the activity and draw before, during, and after pictures.
  5. Share their drawings and discuss where the water goes. The level of the water in the tub before the glass is inserted is lower than when the glass is inserted. It goes up into the tub, but not into the glass as the air in the glass holds it out, themn when the glass is removed, the level of water in the tub goes back down.
  6. Have them edit their pictures, if necessary, to show their answers, discuss, and have them prove them if they desire.
  7. Ask what would scientist call your before, during and after pictures? Models
  8. Ask. Where is the water when the glass is tipped to the side?
  9. Will a boat leak if it has a hole? Maybe and maybe not. If the hole has air trapped above it, then it won't sink. The air will keep the water from coming into the boat. However, if the air isn't trapped above the whole or has a place to leak out, the water will flow in through the hole.
  10. In our next activity, Jars with 2 holes in lids, we can explore holes to see how they operate in this kind of system.

Activity 3 - Jars with 2 holes in lids

Babyfood jar with lid and two holesMaterials :

  1. Baby food jar, several lids for each jar, one with no holes, one with one hole in center, one with two holes - one toward each opposite edge, lab notes & drawing supplies
  2. Lab notes with pictures to look at and describe what would happen for each jar in the four positions.

Focus questions :

  1. What happens when a container with holes is put into water? See scoring guide
  2. What happens when a boat has a hole? If the hole has air trapped above it, then it won't sink. The air will keep the water from coming into the boat. However, if the air isn't trapped above the whole or has a place to leak out, the water will flow in through the hole.

Learning outcomes:

Air takes up space and flows (scoring guide)

Top level

Water will enter depending on the position of the holes.

  • Water will enter if one hole is positioned above the other. If the holes are at equal levels the air will be trapped.
  • When the jar is pushed in up side down there is more pressure on it and the water will not go in. When the jar is pushed in another way there is less pressure and the water will go in.
  • Water enters the bottom hole because there is more pressure on the bottom than on the top.
  • If both holes are at the same depth the pressure is the same and no water will enter.
  • If the bottle traps the air it occupies the space so that the water cannot enter, if the air can exit through one hole, the water will enter through the other.

Water will not enter.

  • Because it is air tight.
  • The jar will float with the lid up so no water will go in.
  • The holes are too small to let in the water. The holes are too small to allow the molecules of water to fit through.
  • The holes will create an air pocket and not permit water to flow into the jar.
  • The pressure from inside the jar is too forceful to let the water in. The air pressure will not allow the water into the jar. The air pressure goes out through the holes keeping the water out. Air pressure will keep the water out. The air pressure is stronger than the water pressure. The air inside is stronger than the water. The air takes up the space and blocks the entrance of the water. Air takes up space and the water will not enter since the air is taking all the space.
  • The air will push against the water causing it to move out of its way (allowing it to stay inside the inverted jar).
  • If the jar is on its side some air will escape, but not enough to let any water in the jar.
  • There is not enough pressure to push the water through the holes.
  • The pressure of pushing the jar into or around in the water will push some water into the jar.
  • As the jar is pulled out of the water the water will be sucked out because more water is being displaced over a bigger area and the jar will come out of the water with out any water inside.

Water will enter through the holes.

  • Water will enter because the jar is being twisted and rotated.
  • The water pressure is greater than the air pressure so the water will push the air out.
  • The water pressure is greater than the air pressure and therefore will push the air out.
  • A vacuum will be created with the release of air from one hole and the water will be sucked into the jar through the other hole.
  • Water will enter when you push the jar down because pushing it down increases the pressure in the jar causing the air to escape leaving room in the jar for water to enter.
  • Pushing the jar down causes pressure to be released through the jar holes causing bubbles to form and water to fill the jar.
  • Pushing the jar down into the water will force water into the jar.
  • Pressure is built up causing bubbles to form and then water will start to enter.
  • If the jar is held under water with the holes on top water will go into the jar and completely fill it, if it's held under long enough.
  • The air will push against the water causing it to move out of its way (and bubble to the surface) of the jar on its side.
  • There would be a little bit of water because of the twisting and turning.
  • The longer the jar is under water the more water that would enter. If it would be left in overnight there would be more.
  • Having a hole on each side helps with pressure being released equally.
  • Bubbles will come from the two holes as the water pushes the air out of the jar.
  • When one hole is out of the water and the other is in the water.

Lower level

Exploration

  1. Put learners into groups.
  2. Ask. What will happen if they put a jar into the water with no holes, one hole, and two holes in the lid? Accept all answers.
  3. Tell. Sort the jars into categories according to amounts of water that will enter. Empty, half, full, full.
  4. Ask. Remember the glass?
  5. Did it made a difference how the glass was put into the water?
  6. Recommend that they try different ways. And if there is a difference, then record the differences in their lab notes.
  7. Have them investigate and draw pictures of what happens.
  8. Encourage them to turn the jars.
  9. Watch them as they record the information. See if they are drawing the position of the holes accurately for the results.

Picture gallery

baby food jar & lid with two holes

Babyfood jar with lid and two holesBabyfood jar with lid and two holes

Babyfood jar submerged horizontally with two holes horizontal
Babyfood jar submerged with two holes horizontal

 

Babyfood jar submerged with two holes vertical
Babyfood jar submerged with two holes vertical
Babyfood jar submerged upside down
Baby food jar submerged upsidedown
Baby food jar two holes submerged vertical
Baby food jar two holes submerged vertical

Invention

  1. Have them share their drawings.
  2. Make a chart with the following categories:
    1. No holes, no water
    2. One hole, no water for small holes, if the hole gets large enogh Water may enter. Might want to experiment with how large the hole needs to be before the water does enter.
    3. Two holes. Depends on the orientation of the holes. see scoring guide with outcomes
  3. Poll the groups and record if there was water in the jars for each category.
  4. Have them explain the results and describe what will happen for each baby food jar in each of the four pictures if it were held under water in those positions. See scoring guide
  5. Have them describe what you believe would happen for the jar lid system if it was held under water in any position. The four positions and all positions between them.
  6. What should we call your explanatin? Model of jars with ... holes ...

Discovery

  1. Ask. How they can use the results.

Activity 4 - Plastic cup with three holes punched in the side

Cup with three holes

Materials

  • Large plastic pop cup, punch one hole at the top, middle, and bottom of a side, cover each hole with masking tape, fill with water, hold over bucket, pull tape from the holes, lab notes & drawing supplies

Focus questions :

  1. What happens when a hole is punched in a container with water?
  2. What causes the water to leak?

Learning outcomes:

  1. Explain how the amount of water above the hole pushes the water out of the hole and the more water the harder it pushes.

Suggested procedures overview :

  1. Observe a container with three holes (one at the top, middle, & bottom) leak water.
  2. Describe how the water leaks.
  3. Explain what causes the water to leak and variables that make a difference (amount of water, size of hole).

Scoring guide for

Top level

  • The water and air above a hole pushes the water below out. The more water the greater the push.
  • Water falls down. Water seeks the lowest area.

Lower level

Exploration

  1. Put learners into groups..
  2. Show them a plastic cup with three holes.
  3. Ask. What will happen when the cup is filled with water and the tape is pulled from the holes? Accept all answers. Water will leak out.
  4. Have them record their predictions in their lab notes.
  5. If they don't predict differences in amounts leaking from the holes, suggest they might want to consider how much water will leak from each hole and what the difference might be.
  6. Pull the tapes.
  7. Have them draw the results

Invention

  1. Ask. What made a difference? The amount of water above, pushing down. Pressure.
  2. Is the amount of water that leaks from each hole different?
  3. How could we find out? Do it again and measure the amount from each hole.
  4. If the holes are positioned above each other, it might be difficult to collect the water from all the holes. Might make another cup with holes distributed around the cup to make it easier to collect the water.
  5. Measure the volume that leaks from each hole and compare them.
  6. How much does the difference depend on the amount of water available above each hole and the pressure?
  7. Make a model ...

Discovery

  1. Ask. Where they could see something similar?

Activity 5 - Remove water from a jar without lifting it from the water

Materials :

  • Baby food jar, plastic tubing, syringe that the tubing will fit, tub of water

Focus questions :

  1. How can the water be removed from a container while it is under water?

Learning outcomes:

  1. Demonstrate and explain air can be used to force water from the cup.

Suggested procedures overview :

  1. Challenge learners to empty a cup filled with water while it is under water.
  2. Give them a syringe and tubing to solve the challenge.
  3. When appropriate suggest to them to use the syringe to blow water into the cup.

Scoring guide for

Top level

  1. Air is matter, has mass, and volume and can displace matter (water).

Lower level

Exploration

  1. Put learners into groups.
  2. Tell. Fill the jar with water and put it upside down in the tub so it is under water and filled with water.
  3. Ask. Is it possible to get the water out of the container without lifting any part of it up and out of the water?
  4. After a few minutes. Suggest they might be able to do so with a syringe and tubing. You can suck water out, but it is replaced by more water. There is no path for air to flow into the glass.
  5. Provide a syringe and tubing to each group and challenge them to get the water out of the jar.
  6. Let the them investigate.
  7. People usually try to suck the water out of the cup. This will not work. It will be up to you to decide if and how to prompt them to try to push air into the cup to push the water out.
  8. After they are successful ...
  9. Tell. Draw a before, during, and after picture to explain what happened.

Invention

  1. Share results.
  2. Have them make a model that includes information that suggest: Air is matter, has mass, and volume and can displace matter (water).

Exploration

  1. Ask. IF You can't suck water out, because it is replaced by more water and there is no path for air to flow into the glass, then what would happen if there was a hole in the bottom of the glass and it was, filled with water, inverted, and put into the tub? The hole would allow the air to flow in and push the water out until the level in the cup was the same as the level in the tub. When yuo try to such out the water in the cup, the air could flowin, but the pressure inside the cup and outside both for the water and air is equal, because of the hole. So depending on the size of the hole the amount should even out as the pressure reaches equalibrium.
  2. Ask. Where could you use what they learned?

Activity 6 - Breaking a stick with air pressure

Materials :

  • Cheap yard stick, full sheet of newspaper

Focus questions :

  1. Will air pressure on piece of newspaper keep a stick whole or will it provide enough force to hold a stick so a karate chop will break it?

Learning outcomes:

  1. Explain how air pressure can be used to hold a stick, or support it, enough so it can be broken.

Suggested procedures overview :

  1. Demonstrate how air pressure can be used to hold a stick, or support it, enough so it can be broken.

Scoring guide for

Top level

  1. Explain the air in the atmosphere is strong enough to hold a sheet of newspaper with enough force to hold a stick so it can be broken.
  2. It is magic.

Lower level

Exploration

  1. Arrange the learners for a demonstration.
  2. Set the yardstick on a table with about two-thirds on the table and one-third hanging over the edge. Place the full sheet of newspaper over the two-thirds of newspaper on the table. Smooth the paper out so it is touching the stick.
  3. Ask them what will happen if you smack the stick on the end that is hanging over the table. Accept all answer. The newspaper will fly up.
  4. Use a quick sharp blow on the end of the stick that is hanging over the edge of the table.

Invention

  1. Ask what happened and how it happened. The stick broke, because the air on the paper exerted enough pressure to hold it in place,
  2. Ask. What other ways does air have force (a push or pull). Any storm with wind. Air guns. All air tools in many engine shops. NASCAR ...

Exploration

  1. See activities 7, 8, 9, & 10 below.

Activity 7 - Straw with water & finger on top

Materials :

  • Straw and cup of water

Focus questions :

  1. How can a straw be made to hold a straw full of water or not?

Learning outcomes:

  1. Explain how atmospheric pressure will hold water in a straw.

Suggested procedures overview :

  1. learners deomonstrate how a straw can be filled with water and the water will remain in the straw or flow out of it.

Scoring guide for

Top level

  1. Explain atmospheric air pressure (force) holds the water in the straw when the finger is on the top of the straw. When the finger is not on the strad the atmospheric pressure (force) is equal on both ends of the straw and therefore the water will flow from the straw.

Lower level

Exploration

  1. Arrange the learners for a demonstration or as pairs.
  2. Ask. What will happen if a straw is put into a cup of water and pulled out? Accept all answers.
  3. Tell. Investigate how can a straw be put into the water and pulled out with and without water in it?
  4. Explore a variety of options.

Invention

  1. What causes the difference? An opening only on the bottom of the straw exerts only a force from the air pressure outside, keeping the water inside. When there is an opening on top of the straw then air can exert pressure on the water in the straw from above and below, equally. With air pressure balanced, gravity causes the waer to fall.
  2. What force cause the water to stay in? air pressure
  3. What force cause the water to flow out? gravity. With the air pressure equal on top and bottom, the mass or weight of the water causes it to fall out.

Exploration

  1. See activities 7, 8, 9, & 10 below.

Activity 8 - Upside down cup of water

Materials :

  • Cup, index card, or oak tag, large enough to cover the opening on the cup, water, and tub of water

Focus questions :

  1. How can a cup full of water be turned upside down so the water will stay in the cup?

Learning outcomes:

  1. Explain how the air pressure from the air in the atmosphere will push on the card with enough force to hold the water in the cup.

Suggested procedures overview :

  1. Use an index card or oak tag to hold water in a cup as it is turned upside down.

Scoring guide for

Top level

  1. Explain the atmospheric air pressure (force) holds the water in the cup by pushing on the card.

Lower level

Exploration

  1. Arrange the learners for a demonstration.
  2. Ask. What will happen if they fill the cup full of water, then place the oak tag square over the mouth, hold it in place, and turn the cup upside down. Accept all answers
  3. Demo the activity.
  4. Ask. What happened and how it happened?

Invention

  1. Ask. What is under the card? air
  2. What could hold the card against the glass? air pressure

How much pressure does air have?

 1 atmosphere (atm), or 29.92 inches of mercury or 1,013.25 hPa,

Think of it in terms of air particles. If the number of particles above a surface increases, there will be more particles to exert a force on the surface below and the pressure increases. The opposite is also true, if the number of air particles above the surface decreases, the pressure will decrease.

Atmospheric pressure is measured with an instrument called a barometer, which is why atmospheric pressure is also referred to as barometric pressure.

As an example, consider a square unit of area, like say 1 square inch. At sea level, on average, the weight of the air above one square inch unit area would weigh 14.7 pounds! Or the air pressure of the air on an area would be 14.7 pounds on every square inch.

Meteorologists use a metric unit for pressure called a millibar. Average pressure at sea level is 1013.25 millbars or 14.7 pounds per square inch.

Check the size of this square and correct it if necessary.
Square inch - maybe
  1. Ask. Can think of other examples of air having force.
  2. See activity 9, & 10 below.

Exploration

    1. See activities 7, 8, 9, & 10 below.

Activity 9 - Challenge: How can air lift a person?

Materials :

  • Plastic bag, air pump, duct tape, board, chair, person

Focus questions :

  1. Is air have enough force to lift a person?

Learning outcomes:

  1. Explain how air has enough force to move a person or anything that has less force.

Suggested procedures overview :

  1. Challenge learners to create a way to lift the person.
  2. If necessary lead them to use the air pump to pump air into the plastic bag, which will provide enough force to lift the person.

Scoring guide for

Top level

  1. The air pumped into the plastic bag has a force greater than the force of the person pushing down on the plastic. Therefore, the plastic bag pushes the person up.

Lower level

Exploration

  1. Arrange the learners for a demonstration.
  2. Ask. How can the materials be used to lift a person?

Invention

  1. How is air pressure used in technology?
  2. See activity 10 below.

Exploration

  1. See activities 7, 8, 9, & 10 below.

Activity 10 - Crushing a can with air

Metal can with lid

Materials

  • Hot water, can with screw on lid, half-gallon can works well. Could also use plastic bottle, but the sight and sound of metal being crushed has a slightly bigger impact, ice. See picture gallery for plastic bottle crush.
  • Create safe conditons for handling hot water.

Focus questions :

  1. Is the atmosphere air strong enough to crush a can?

Learning outcomes:

  1. Explain how air in the atmosphere has enough force to crush a can when the air inside pushes out with less force than the atmosphere (air outside).

Suggested procedures overview :

  1. Challenge learners to create a way to crush a can with hot water and ice.
  2. If necessary lead them to use a temperature difference to change the energy of the air inside the can so there is less force pusing out.

Scoring guide for

Top level

  1. The hot water causes the air inside to expand. When the lid is put on the can and ice is added the air inside contracts and the force of the atmosphere on the outside is greater than the force inside, causing the can to crush.

Lower level

Bottle crushing album

Adding hot water to the bottle.

Bottle with quarter inch hot water

Bottle with hot water

Capping (sealing) the bottle and setting it ready to cool with ice.

Plastic bottle with hot water sealed

Plastic bottle with hot water sealed

Place a cold ice pack on the bottle.

Bottle with ice pack
Bottle with ice pack

Crushing begins ...

Bottle with ice pack
Bottle with ice pack

Crushing continues...

Plastic bottle being crushed
PLastic bottle being crushed

Done! Notice the results!

Plastic bottle after
Bottle crushed

Insight ... let's see what happens if the bottle is placed on the ice pack!

Ready to go

Plastic bottle with hot water sealed
It is starting to crush
Plastic bottle beginning to crush on ice pack
Still crushing
Bottle being crushed
Even more
Bottle being crushed
Side view

Crushed bottle on ice pack sideways

While the bottle crushed about the same with the ice on the bottom as on the top it will take longer with ice on the bottom.

Exploration

  1. Arrange the learners for a demonstration.
  2. Ask. How can the materials be used to crush the can? Take hot water [almost at boiling point] and pour enough to cover the bottom to about a quarter inch level. Slowly and quickly swish the the water around and wait a couple of seconds for the air inside to heat up and exit. Put the lid or cap on and tighen it. Can float the can in an ice bath or lay it down with the largest surface area up and place ice on top. Or see pictures of using a small plastic bottle if you don't have a metal can..

Invention

  1. Explain how the can was crushed. When the can is heated it and the air inside are heated. Think of all those air particles moving around and bouncing off the can. The more energy each particle has, the harder it hits other particles and the can exerting more pressure. If they have less energy, the hits have less force and results in less pressure. Also as the air inside was heated it expanded and pushed some of it out of the can. When the lid was put on the can, the amount of air inside could not change. The air, like all gases, will spread out and fill the space it is contained in. Therefore, the spaces between air particles will change as the temperature changes. Higher temperature, more space. Lower temperature less space. Therefore, When the air was in the hot can, the space between the particles was increased. When it was cooled the spaces between the particles was decreased. And related to that spacing is the pressure it can exert on its container. Therefore, temperature and pressure are related. Soooo... When the temperature of the air was hot the space between the particles is more (pushing air outof the container) and the pressure would be higher. When the can is sealed the amount of air inside can't change. As the temperature lowers it takes up less space and the pressure decreases. As the pressure inside decreases it can not push on the inside of the can with enough force to leep the outside pressure from crushing the can.
  2. Work in groups to make a model that explains this. Draw before and after pictures and explain ...

Discovery

  1. How is air pressure used in technology?
  2. See heat energy activities.

Activity 11 - Looking inside a balloon

Materials :

  • Balloons, looking inside a balloon apparatus
Look inside balloon app

Focus questions :

  1. Can you inflate up a balloon, keep it inflated, and look inside through its opening.
Look inside app with directions

Learning outcomes:

  1. Explain how the air pressure in the app balances with with the air pressure outside and keeps the balloon shape as blown up.

Suggested procedures overview :

  1. Present the focus question as a challenge.
  2. Ask. Is the Challenge possible? If so how?
  3. Demonstrate how to blow up the balloon, seal the bottom hole, and show that it doesn't deflate completely.
  4. Discuss the relationship of the pressures on both side of the balloon.

Scoring guide for

Top level

  1. The air on the inside and outside of the balloon are equal and supports the balloon so it is inflated. .

Lower level

Exploration

  1. Arrange the learners for a demonstration.
  2. Present the focus question as a challenge.
  3. Ask. Is the Challenge possible?
  4. If so how?
  5. Demonstrate how to blow up the balloon, seal the bottom hole, and show that it doesn't deflate completely.

Invention

  1. Discuss the relationship of the pressures on both side of the balloon.
  2. How might this idea be used in industry?

Exploration

  1. Review previous activities 7, 8, 9, & 10.

 

 

Lab Notes for activities

Activity 1 - Balloons and water

Materials :

  • Balloons inflated to different sizes (at least three), tub of water, science journal or drawing materials

Focus questions :

What is inside a balloon?

 

What happens when balloons are put into water?

 

 

Before

 

 

 

 

 

 

During

 

 

 

 

 

 

After

 

 

 

Activity 2 - Inverted cup without & with paper towel under water

Paper towel and baby food jarMaterials :

  • Clear cup or glass, tub of water, paper towels, lab notes & drawing materials

Focus questions :

What happens to an empty glass when it is put into water?

 

 

 

How do you put a paper towel under water and keep it dry?

 

 

 

 

Before

 

 

 

 

 

 

During

 

 

 

 

 

 

After

 

 

Activity 3 Jars with 2 holes in lids

Materials : Baby food jar, several lids for each jar, one with no holes, one with one hole in center, one with two holes - one toward each opposite edge, lab notes & drawing supplies

Baby food jar submerged with jar horizontal and two holes almost horizontal
Babyfood jar submerged with two holes horizontal
Baby food jar submerged with jar vertical and two holes horizontal
Babyfood jar submerged with two holes vertical

Procedure:

What will happen for jars held under water with ...

No holes in the lid ...

With one hole in the lid ...

With two holes in the lid ...

Why do you think this?

 

Investigate with jars and lids and record the results.

 

 

 

Describe what will happen for each baby food jar in each of the four pictures if it were held under water in those positions.

Jar underwater pic jar 2

Jar 1 - will

 

 

 

Jar 2 - will

 

 

 

 

jar 3 jar 4

Jar 3 - will

 

 

 

Jar 4

 

 

 

 

Describe what you believe would happen for the jar lid system if it was held under water in any position. The four positions and all positions between them.

 

Activity 4 - Plastic cup with three holes punched in the side

Materials :

  • Clear cup or glass, tub of water, paper towels, lab notes & drawing materials

Focus questions :

What happens when a hole is punched in a container with water?

 

What causes the water to leak?

 

 

 

 

 

 

 

 

 

Activity 5 - Remove water from a jar without lifting it from the water

Materials :

  • Baby food jar, plastic tubing, syringe that the tubing will fit, tub of water

Focus question :

How can the water be removed from a container while it is under water?

 

 

 

 

 

 

 

 

 

 

 

 

Activity 6 - Stick breaking

Materials :

  • Cheap yard stick, full sheet of newspaper

Focus question :

Will air pressure on a piece of newspaper keep a stick whole or will it provide enough force to hold a stick so a karate chop will break it?

 

 

 

 

 

 

 

 

 

 

 

 

Activity 7 - Straw with water and finger on top

Materials :

  • Straw and cup of water

Focus question :

How can a straw be made to hold a straw full of water or not?

 

 

 

 

 

 

 

 

 

 

 

 

Activity 8 - Upside down cup of water

Materials :

  • Cup, index card, or oak tag, large enough to cover the opening on the cup, water, and tub

Focus question :

How can a cup full of water be turned upside down so the water will stay in the cup?

 

 

 

Background information for air pressure

How much pressure does air have?

 1 atmosphere (atm), or 29.92 inches of mercury or 1,013.52 hPa (hectoPascals, also called millibars)

Think of it in terms of air particles. If the number of particles above a surface increases, there will be more particles to exert a force on the surface below and the pressure increases. The opposite is also true, if the number of air particles above the surface decreases, the pressure will decrease.

Atmospheric pressure is measured with an instrument called a barometer, which is why atmospheric pressure is also referred to as barometric pressure.

As an example, consider a square unit of area, like say 1 square inch. At sea level, on average, the weight of the air above one square inch unit area would weigh 14.7 pounds! Or the air pressure of the air on an area would be 14.7 pounds on every square inch.

Meteorologists use a metric unit for pressure called a millibar. Average pressure at sea level is 1013.52 millbars or 14.7 pounds per square inch.

Check the size of this square and correct it if necessary.
Square inch - maybe

 

 

 

 

 

 

 

 

Activity 9 - Challenge: How can air lift a person?

Materials :

  • Plastic bag, air pump, duct tape, board, chair, person.

Focus question :

How can you use air to lift a person?

 

 

 

 

 

 

 

 

 

 

Activity 10 - Crushing a can with air

Materials :

  • Hot water, can with screw on lid, ice.

 

Focus question :

How can air pressure crush a can?

 

 

 

 

 

 

 

 

 

 

 

Activity 11 - Lookin inside a balloon

Materials :

  • Balloons & ballon app
Looking insdie a balloon app
Looking inside a balloon app

Challenge :

How can you look inside an inflated balloon?

 

 

 

 

 

 

 

 

 

 

 

 

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Science directories


Dr. Robert Sweetland's notes
homeofbob.com & thehob.net