lesson 13: capillary carnations

166LESSON 1: Goofy Putty 166LESSON 1: Goofy PuttyYou Be The Chemist Activity Guides | page 166You Be The Chemist Activity Guides | page 166You Be The Chemist Activity Guides | page 166You Be The Chemist® Activity Guide | page 166

LESSON 13: Capillary CarnationsESTIMATED TIME Setup: 5–10 minutes | Procedure:Allow at least 24 hours to make periodic observations.

• DESCRIPTIONPlace white carnations in colored water to make theflower petals change color.

• OBJECTIVEThis lesson demonstrates capillary action in plants andintroduces the forces involved in the process. Studentsuse food coloring to help visualize the movement ofwater into and through a plant. The lesson can beextended to discuss the molecular structure andproperties of water.

• CONTENT TOPICSScientific inquiry; states of matter; properties ofmatter; attractive forces (surface tension, adhesion,cohesion)

• MATERIALSo White carnation flowers

o Clear plastic cups o Water o Food coloring o Scissors and/or knife

Always remember to use the appropriate safetyequipment when conducting your experiment.

Refer to the Safety First section in the Resource Guide on pages 391–393 for more detailed information aboutsafety in the classroom.

Jump ahead to page 169 to view theExperimental Procedure.

OBSERVATION & RESEARCH

BACKGROUNDMatter exists primarily as a solid, liquid, or gas on the

earth. Solids have a definite volume and a definite shape.

Examples of solids are chairs, books, and trees. Liquids

have a definite volume but no definite shape. Examples of

liquids are water and orange juice. Gases have no definite

shape and no definite volume. Examples of gases are the

oxygen we breathe and the helium that fills balloons.

Along with differences in shape and volume, the

different states of matter have other unique properties.

For example, capillary action and surface tension are

unique properties of liquids.

Capillary action, or capillarity, is the movement of liquids

upward through a narrow tube, cylinder, or permeable

substance because of the cohesive and adhesive forces

interacting between the liquid and the surface. Cohesion

is the attractive force that exists between like particles

in a certain liquid. (It’s the attraction that causes like

molecules to stick together.) Thus, water molecules are

attracted to other water molecules.

Likewise, surface tension is a property of liquids that

describes the attraction of liquid particles at the surface.

The strong attraction (cohesion) of particles at the

surface of the liquid creates a surface “film” that makes

NATIONAL SCIENCE EDUCATION STANDARDS SUBJECT MATTERThis lesson applies both Dimension 1: Scientific and Engineering Practices and Dimension 2: Crosscutting Conceptsfrom “A Framework for K–12 Science Education,” established as a guide for the updated National Science EducationStandards. In addition, this lesson covers the following Disciplinary Core Ideas from that framework: • PS1.A: Structure and Properties of Matter • PS2.A: Forces and Motion • LS1.A: Structure and Function • ETS2.B: Influence of Engineering, Technology, and Science on Society and the Natural World (see Analysis & Conclusion)

You Be The Chemist® Activity Guide | page 167

LESSON 13: Capillary Carnationsmoving an object through the surface of a liquid more

difficult than moving the object when it is completely

submerged in the liquid. Surface tension is also the

reason liquids tend to keep a low surface area. For

example, water droplets will tend to form into a sphere

rather than spreading out flat.

Conversely, adhesion is

the force of attraction

between unlike

molecules. It’s the

force that causes

water molecules to

stick to the inside

of a glass. The

forces of capillary

action are strong

enough to move the liquid

upward against the force of gravity.

All plants need water to survive, and most plants get

that water from the soil. Capillary action helps to move

water, and the nutrients dissolved in the water, up into

the plant’s roots and through all parts of the plant.

The water gets into the plant’s roots and adheres to the

plant tissue. The plant tissue attracts the water molecules

(because of adhesion), pulling the water up into the

plant. As one water molecule climbs, the cohesive

attraction to other water molecules pulls those molecules

up the stem as well. Why does all the water move

upward in the entire stem, rather than just some water

molecules moving upward along the edges? The surface

tension of the water keeps the surface intact, so the

whole liquid surface is dragged upward, pulling the rest

of the water molecules upward behind it.

HYPOTHESIS

uWhen the stems of white carnation

flowers are placed in colored water, the

colored water will move up through the plant,

causing the petals to change color.

CONNECT TO THE YOU BE THECHEMIST CHALLENGE

For additional background information, please

review CEF’s Challenge study materials online at

http://www.chemed.org/ybtc/challenge/study.aspx.

• Additional information on states and properties ofmatter, including surface tension, can be found inthe Classification of Matter section of CEF’sPassport to Science Exploration: The Core ofChemistry.

DIFFERENTIATION IN THE CLASSROOM

LOWER GRADE LEVELS/BEGINNERSPerform the experiment as described on page 169, butspend more time on the states and properties of matter.Show pictures of different items—a chair, milk, a balloon.(A balloon is solid, but what fills the balloon?) Ask thestudents to identify the state of matter for each substanceand describe the differences between the states.

Likewise, focus more on the different properties of matter,specifically the properties of liquids. Pour a little water ona desk to illustrate the cohesive attraction of watermolecules. The water will form droplets. Then tilt thedesk slowly so the water flows off the edge. Does it lingerat the side of the desk before falling to the ground?Discuss how cohesion and adhesion play a part.

Fun FactIn ancient Greece,

carnations were used to

make ceremonial crowns.

In this experiment, the adhesive and cohesive forces

pull the water up into the carnation against the force of

gravity. This action can be proven by using food

coloring. The food coloring is drawn upward into the

plant and its petals with the water.

FORMULAS & EQUATIONSWater is a liquid substance that is essential to the

survival of plants and animals.

The chemical formula for pure water is H2O.

This formula illustrates that a molecule of water is

comprised of two hydrogen atoms and one oxygen atom.

http://www.chemed.org/ybtc/challenge/study.aspx


LESSON 13: Capillary Carnations

HIGHER GRADE LEVELS/ADVANCED STUDENTSDESCRIPTIONPlace white carnations in colored water to make the

flower petals change color.

OBJECTIVEThis lesson demonstrates capillary action in plants and

explores the structure of plants and properties of water.

Students use food coloring to help visualize the

movement of water into and through a plant.

OBSERVATION & RESEARCH Matter exists primarily in three states on the earth—solid,

liquid, or gas, and each state of matter has unique

properties. The properties of matter are characteristics

that describe a particular substance. For example, solids

have a definite shape. Likewise, liquids are often

described by certain unique properties, such as surface

tension.

Capillary action, or capillarity, is the movement of liquids

upward through a narrow tube, cylinder, or permeable

substance because of the cohesive and adhesive forces

interacting between the liquid and the surface. Cohesion

is the attractive force that exists between like particles in

a certain liquid. (It’s the attraction that causes like

molecules to stick together.)

Surface tension is another property of liquids that results

from cohesion. The strong attraction (cohesion) of

particles at the surface of the liquid creates a surface

“film” that makes moving an object through the surface

of a liquid more difficult than moving the object when it

is completely submerged in the liquid. Surface tension is

also the reason liquids tend to keep a low surface area.

For example, water droplets will tend to form into a

sphere rather than spreading out flat.

Conversely, adhesion is the force of attraction between

unlike molecules. It’s the force that causes water

molecules to stick to the inside of a glass. The forces of

capillary action are strong enough to move the liquid

upward against the force of gravity.

All plants need water to survive, and most plants get that

water from the soil. Capillary action helps to move water,

and the nutrients dissolved in the water, up into the

plant’s roots and through all parts of the plant. The water

is attracted to the plant’s roots as a result of adhesion.

It then moves across the root cells to a certain type of

plant tissue called xylem. Xylem is a complex plant tissue

made up of vessels (or small hollow tubes) that transport

water and dissolved minerals through the plant. Xylem

also provides structural support to the plant.

The attraction of the water molecules to the xylem

causes the water to adhere to the sides of these tiny tubes,

climbing up the sides as more water molecules move

toward the tissue. The water, however, does not just move

upward along the sides of the xylem. It moves up through

the entire tube. The surface tension of the water keeps the

surface intact, so the whole liquid surface is dragged

upward. Cohesion then causes the rest of the water

molecules below the surface to be pulled upward as well.

In this experiment, the adhesive and cohesive forces pull

the water up into the carnation against the force of

gravity. This action can be seen by using food coloring.

The food coloring is drawn upward into the plant and its

petals with the water.

DIFFERENTIATION IN THE CLASSROOM

CONNECT TO THE YOU BE THECHEMIST CHALLENGE

For additional background information, pleasereview CEF’s Challenge study materials online athttp://www.chemed.org/ybtc/challenge/study.aspx.

• Additional information on states and properties ofmatter, including surface tension, can be found inthe Classification of Matter section of CEF’sPassport to Science Exploration: The Core ofChemistry.

http://www.chemed.org/ybtc/challenge/study.aspx


LESSON 13: Capillary CarnationsEXPERIMENTATION

EXPERIMENTAL PROCEDURE

1. Fill a cup halfway with water and add 20–30

drops of food coloring.

2. Cut two inches off the bottom of each carnation

stem. Then, place the carnations’ stems in the

colored water.

3. Wait several hours or even until the next day to

observe the results.

4. To dye one carnation’s petals two different colors,

use a knife or scissors to split the stem lengthwise

into two pieces. Do not split the entire stem; stop

about 2–3 inches from the top of the stem.

5. Place the separated sections of the stem in different

colored water solutions, and wait several hours or

even until the next day to observe the results.

Always be careful when using scissors and

other sharp objects. When splitting the

carnations’ stems in half, it is best to do this for the

students.

DATA COLLECTION

Have students record data in their science notebooks or on the

following activity sheet. How do plants move water from the

soil into all parts of the plant? How quickly does the water

move through the plant? You can use the table in the activity

sheet (or a similar one of your own) for students to record

their data.

As the students perform the experiment, challenge them to identify the independent, dependent, and controlled

variables, as well as whether there is a control setup for the experiment. (Hint: If you add food coloring to the water,

will the color of the petals change?) Review the information in the Scientific Inquiry section on pages 14–16 to

discuss variables.


LESSON 13: Capillary CarnationsANALYSIS & CONCLUSION

Use the questions from the activity sheet or your own

questions to discuss the experimental data. Ask students

to determine whether they should accept or reject their

hypotheses. Review the information in the Scientific

Inquiry section on pages 14–16 to discuss valid and

invalid hypotheses.

ASSESSMENT/GOALS

Upon completion of this lesson, students should be able

to …

• Apply a scientific inquiry process and perform anexperiment.

• Differentiate between the different states of matter.

• Describe capillary action and the attractive forces ofcohesion, adhesion, and surface tension.

• Explain the importance of capillary action in nature.

• Explain the purpose of xylem in plants (see Differentiation in the Classroom).

MODIFICATIONS/EXTENSIONS

Modifications and extensions provide alternative methods

for performing the lesson or similar lessons. They also

introduce ways to expand on the content topics presented

and think beyond those topics. Use the following

examples or have a discussion to generate other ideas

as a class.

• Before the lesson, take a paper towel and hold thebottom of it in a cup of water. Have the students watchas water rises up the paper towel. Ask your students ifthey know how this is possible. Discuss how water canrise up against the force of gravity. Most will knowthat the water is being absorbed by the paper towel,but they may not know that it is because of capillaryaction. The water adheres to the fibers in the papertowel and climbs up the paper towel, pulling otherwater molecules upward as well because of cohesion.

• After the experiment, cut the stems of the carnationsand have the students observe the tiny tubes in theplant. Magnifying glasses may help them to see thetubes.

REAL-WORLD APPLICATIONS

• Most plants get the water they need to survive throughtheir roots. While some plants can absorb waterthrough their leaves, water from the ground generallycontains other nutrients that are useful to the plant. By obtaining water from the ground, the minerals andnutrients dissolved in the ground water are pulled upinto the plant as well. As a result, it is important towater the ground where plants grow. If you only waterthe leaves or top of the plant, the plant will not getenough water to survive.

• Blood is mostly water, so the forces of adhesion,cohesion, and surface tension, and therefore capillaryaction, can be observed with blood. If you prick yourfinger, the blood will form droplets. Likewise, if theedge of a sterile gauze pad touches the blood, the bloodwill quickly move up through the fibers of the gauze.

COMMUNICATION

Discuss the results as a class and review the activity sheet.

Review the information in the Scientific Inquiry section on

pages 14–16 to discuss the importance of communication

to scientific progress.

You Be The Chemist Activity Guides | page 171You Be The Chemist® Activity Guide | page 171

LESSON 13 ACTIVITY SHEET: Capillary Carnations

OBSERVE & RESEARCH

1. Write down the materials you see. ____________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

2. How might these materials be used? __________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an

image of the example.

Term Definition Example (write or add image)

Solid

Liquid

Gas

Capillary action

Cohesion

Surface tension

Adhesion

4. Consider what will occur if white carnations are placed in colored water and why.

uWrite your hypothesis. ______________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________



ANALYZE & CONCLUDE

1. Record your observations of the carnations’ appearance in the table below. Record the day and time of your

observations. For example, Monday, 10:00 a.m.

PERFORM YOUR EXPERIMENT

1. Fill a cup halfway with water. Add 20–30 drops of food coloring to the cup of water.

2. Use scissors to cut two inches off the bottoms of the stems. Then, place the carnations’ stems in the colored water.

3. Wait several hours or until the next day. Observe the results.

4. Try dyeing one carnation different colors. Your teacher will provide a carnation with the stem split lengthwise in two

pieces. Place the separated parts of the stem in different colored water solutions. Wait several hours or until the

next day. Observe the results.

Always be careful when using scissors and other sharp objects.

Day and Time Observations (color, healthy/wilted, etc.)

You Be The Chemist Activity Guides | page 173You Be The Chemist® Activity Guide | page 173


2. What does the carnation look like before it is placed in the colored water? __________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. Describe the carnation after it has been in the colored water for a few hours. ________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

4.What do you think caused the change? ________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

5.What forces do you think are causing this to occur? __________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

6. After you split the stem of a carnation, what do you see? ________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

7. Is your hypothesis valid? Why or why not? If not, what would be your next steps? ____________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________



2. When you water a plant, why would you soak the soil around the plant instead of sprinkling water on the plant’s

leaves? ____________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. The water absorbed by plant roots is used in a process by which plants make their own food. What is this process

called? Write the chemical equation for the reaction. Where does this process take place within the plant?

______________________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

EXPAND YOUR KNOWLEDGE—ADVANCED

1. Define the following key term. Then, provide an example of it by writing the example or drawing/pasting an image

of the example.


Xylem


LESSON 13 ACTIVITY SHEET: Capillary CarnationsANSWER KEY Below are suggested answers. Other answers may also be acceptable.

OBSERVE & RESEARCH

1. Write down the materials you see. ____________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

2. How might these materials be used? __________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an

image of the example.


Solid A state of matter characterized by a definite volumeand definite shape.

LiquidA state of matter that has a definite volume but nodefinite shape; a liquid will take the shape of thecontainer that holds it, filling the bottom first.

GasA state of matter that has no definite volume orshape; a gas will take the shape of the containerthat holds it, filling the entire container.

Capillary actionThe ability of a substance to be drawn (possiblyupward) through a tiny tube or vessel due toadhesive and cohesive forces; also known ascapillarity.

CohesionAn attractive force that holds atoms or ions of asingle body together; an attraction betweenparticles of the same kind.

Surface tensionA property of liquids that describes the attraction ofliquid particles at the surface; the strong attractionof particles at the surface of a liquid creates asurface “film.”

Adhesion An attractive force that holds atoms or ions ofdifferent substances together.

4. Consider what will occur if white carnations are placed in colored water and why.

uWrite your hypothesis. ______________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________

White carnations may be used as decorations. Plastic cups may be used to hold a substance.

Water may be used to drink, bathe, or clean. Food coloring may be used to dye a substance. Scissors may be used to cut materials. These

materials may be used to change the color of white carnations and demonstrate capillary action.

White carnations, plastic cups, water, food coloring, scissors …

White carnation petals will turn the color of the dyed water because of capillary

action within the plant.



ANALYZE & CONCLUDE

1. Record your observations of the carnations’ appearance in the table below. Record the day and time of your

observations. For example, Monday, 10:00 a.m.

PERFORM YOUR EXPERIMENT

1. Fill a cup halfway with water. Add 20–30 drops of food coloring to the cup of water.

2. Use scissors to cut two inches off the bottoms of the stems. Then, place the carnations’ stems in the colored water.

3. Wait several hours or until the next day. Observe the results.

4. Try dyeing one carnation different colors. Your teacher will provide a carnation with the stem split lengthwise in two

pieces. Place the separated parts of the stem in different colored water solutions. Wait several hours or until the

next day. Observe the results.

Always be careful when using scissors and other sharp objects.

Day and Time Observations (color, healthy/wilted, etc.)

Answers will vary Answers will vary



2. What does the carnation look like before it is placed in the colored water? __________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. Describe the carnation after it has been in the colored water for a few hours. ________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

4.What do you think caused the change? ________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

5.What forces do you think are causing this to occur? __________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

6. After you split the stem of a carnation, what do you see? ________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

7. Is your hypothesis valid? Why or why not? If not, what would be your next steps? ____________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

The carnation looks healthy. It is upright in the

cup, and the petals are white.

The bottoms of the petals begin to show the

color of the water.

Capillary action drew the colored water up into the carnation, dyeing the petals.

The forces of cohesion and adhesion cause the capillary action to occur.

The inside of the carnation stem shows tiny strands of color.

These strands of color are the xylem that are transporting the colored water through the plant.

Answer 1: Valid because the data support my hypothesis.

Answer 2: Invalid because the data do not support my hypothesis. I would reject my hypothesis and could form a new one, such as …



2. When you water a plant, why would you soak the soil around the plant instead of sprinkling water on the plant’s

leaves? ____________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

3. The water absorbed by plant roots is used in a process by which plants make their own food. What is this process

called? Write the chemical equation for the reaction. Where does this process take place within the plant?

______________________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

______________________________________________________________________________________________________

EXPAND YOUR KNOWLEDGE—ADVANCEDHave students complete this section if you used the advanced differentiation information, or challenge them to find the answers to these

questions at home and discuss how these terms relate to the experiment in class the next day.

1. Define the following key term. Then, provide an example of it by writing the example or drawing/pasting an image

of the example.


XylemA complex plant tissue made up of networks of vessels (or small hollow tubes) that transport water and dissolved minerals through the plant; provides structural support tothe plant.

You soak the soil around the plant with water because plants absorb water through their roots, which are in the ground. The water is

then transported throughout the plant by tiny vessels. If you just sprinkled the water on the plants’ leaves, the plant may not absorb enough

water to survive.

Photosynthesis is the process by which plants make their own food. The chemical equation for the reaction is

6CO2 + 6H2O + sunlight (energy) g C6H12O6 + 6O2. This process occurs within the chloroplasts found in the plant cells.

lesson 13: capillary carnations

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