chemistry booklet final (august 21).docx

A STEM Education Girl Scout Gold Award Project (Student Booklet)

Table of Contents:

1) The Scientific Process: Is There a Correct Way in which to Research? (Page 3)

2) Let’s Build an Atom! (Pages 4-8)

3) Ionic vs. Covalent Bonds (Pages 9-12)

4) How Many Drops? (Pages 13-17)

5) What are the States of Matter? (Pages 18-22)

6) Chemical Reactions: Hot vs. Cold (Pages 23-26)

7) Reactions that are Hot? (Pages 27-30)

8) Reactions that are Cold? (Pages 31-34)

9) Let’s Test for Starch! (Pages 35-40)

10) Let’s Blow up a Balloon! (Pages 41-45)

11) How Does Surface Area Affect a Reaction? (Pages 46-51)

12) Glossary (Pages 52-53)

13) Bibliography (Pages 54-55)

©2015 Sarah Depew 2

The Scientific Process: Is There a Correct Way in which to Research?

Science is universal. An experiment that is conducted in the United States of America may lead to further research in Australia, London, or even China! This globalization, or global spreading, of information means many types of scientists must be able to "speak" the same scientific language. This language comes in the form of a six-step procedure, called the scientific process, and is what many scientists use when they conduct their experiments.

First, a scientist asks a question he or she would like to answer. Questions are vitally important to science, because inquiry is the way in which man furthers their spheres of knowledge. As questions are posed, the scientist settles on the specific idea he or she would like to know more about.

Then, in order to gather information about the topic, the scientist investigates background information concerning the question. Analysis permits the researcher to see if someone has conducted the experiment previously. Too, this process of investigation means the researcher becomes even more familiar with certain aspects of the experiment and learns about specific areas about which he or she may want to know more.

After he or she has done as much research that scientist deems necessary, the researcher develops a hypothesis. A hypothesis is a statement in the form of "if….then" that intelligently predicts the outcome of the experiment using background information from the research and intelligent guessing. For example, one hypothesis a scientist could use in order to study the effects of water on plant health would be "if I do not water my plant for one week, then it will die." Hypotheses solidify the question in a testable manner where it can be either proven or disproven.

Next, the scientist tests his or her hypothesis by conducting an experiment. Usually, scientists have to set up and design experiments themselves. However, in this booklet, I have written multiple experiments for you and you do neither have to set up nor design the experiments.

Finally, scientists must collect their data, analyze it, and present their findings. The data he or she collects during the experiment permits the scientist to either prove or disprove the hypothesis. The whole point of scientific inquiry is to investigate and learn about some topic that interests you; by proving or disproving a hypothesis, your path of learning is honed and refined.

Ever since a man named Francis Bacon developed a standardized method of conducting scientific experiments and research, many scientists have followed his scientific process. This step-by-step means of conducting experiments uses six basic steps to layout scientific inquiry in a standardized manner. Although the topic is often different, the scientific process organizes experiments in a reproducible and relatable manner.


Let’s Build an Atom!

Background for Experiment:

The smallest building blocks of matter are atoms. When atoms combine, they form molecules.

Atoms are made up of three different components: protons, neutrons, and electrons.

Protons and neutrons make up the central part of an atom, which is called the nucleus.

Electrons travel around the nucleus.

To symbolize the location and energy level of an atom’s electrons, scientists use circular-shaped orbitals.

In an atom, two electrons can be in the first orbital and eight electrons can exist in all subsequent orbitals. In carbon-12, the atom you will be building in this experiment, its first orbital houses two electrons and its second orbital houses four electrons, or six electrons total.

Definitions:

Atom: The most basic, fundamental component of matter. Molecule: A substance that forms from the combination of two or more atoms. Proton: The positively charged part of an atom. Neutron: The uncharged, or neutrally charged, part of an atom. Electron: The negatively charged part of an atom. Nucleus: The central part of an atom that is made up of both protons and neutrons. Orbital: A way of drawing the energy level(s) at which an atom’s electrons exist.

Materials List:

Craft Glue

Multicolored jelly beans (any brand, but there must be at least three colors)

Two pieces of blank, white paper

Colored pens, markers, or crayons


Procedure:

1) First, lay out all the required materials that were listed in the materials list located above. (Your items may vary from the ones found below.)

1) Next, you should open the bag of jelly beans.

2) After opening the bag, count out six jelly beans of the three different required colors.


3) Once you have your three colors of jelly beans, organize each colored group of six jelly beans in its own pile on the first piece of paper.

4) Following this, place the piece of paper with the jelly bean piles on it to your right.

5) Next, take the second piece of white paper and lay it in front of you.

6) In the center of this piece of white paper, glue a mixture of two of the colors of jelly beans. This is your nucleus. In total, there should be twelve glued jelly beans that are two different colors and one color of six unglued jelly beans remaining on the first piece of paper to your right.

7) Next, draw two orbitals around the nucleus you just created. Each orbital should be approximately the shape of a circle. When drawing the orbitals, you should draw the first orbital closer to the nucleus. This first orbital should be smaller than the second orbital, which you draw further away from the nucleus.

Please note that I labeled the parts of the photograph included below. You do not have to label your picture if you do not want to do so.


8) In the first circular orbital, glue two of the remaining colored jelly beans. With this step, remember that the first orbital can only house two electrons.

9) After completing step nine, glue the remaining four electrons in the second orbital.


10) Finally, using your completed project, answer the comprehension questions.

Comprehension Questions:

Today, you built a carbon-12 atom! Carbon is one of the most important elements in the universe and distinguishes living creatures from nonliving objects. Now, you will answer a few questions to test your knowledge on how atoms are built!

1) How many protons did you glue in your nucleus? How many neutrons? What color of jelly bean did you use to represent each atomic particle?

2) How many electron orbitals did you have in your drawing? How many electrons were in each orbital? How many total electrons does a neutral carbon atom have?

3) First, count the number of total neutrons and protons you have in the nucleus of your atom. How many total protons and neutrons do you have?

4) What do you think would happen if you added two more protons? Remember that each proton has a +1 positive charge. Hypothetically, how would a positively charged atomic particle affect the charge of the atom in question?


Ionic vs. Covalent Bonds


There are two types of molecular interaction: intramolecular bonds and intermolecular forces. This experiment illustrates intramolecular bonding.

Intramolecular bonds include ionic bonds, covalent bonds, and metallic bonds. Each of these types of bonds occurs within molecules. As a result, intramolecular bonds affect the chemical properties of compounds.

Ionic bonds create ions. In other words, since atoms that engage in ionic bonding are so horrible at sharing electrons, one atom or part of the molecule becomes positively charged and one part of the atom or molecule becomes negatively charged. As a result, these ions can create additional ionic bonds with other ions to form interesting and intricate structures!

Covalent bonds, on the other hand, are really good at sharing electrons! As a result, molecules that are covalently bonded share their electrons between their atoms.

Definitions:

Intramolecular bonds: This is a type of bonding that occurs within molecules on the atomic level.

Intermolecular forces: This is a type of bonding that occurs between molecules. Ionic bonds: A type of intramolecular bond in which one atom transfers electrons to

another atom. Covalent bonds: A type of intramolecular bond in which atoms share electrons between

one another. Ion: An either positively or negatively charged particle.

Materials List:

Gumdrops (you have to at least have four different colors)

Toothpicks (at least fifteen)

Pen (to record data)


Procedure:

1) Lay out all the materials in front of you on a table. (Your items may vary from the ones found below.)

2) Open any external packaging, then count out one color of one gumdrop, two of another color of gumdrop, five of two other colors of gumdrops, and fifteen toothpicks.


3) After you have done this, choose the gumdrop pile where you counted out one color, the gumdrop pile where you counted out two colors, and two toothpicks.

4) Next, assemble the gumdrops and the toothpicks to look like the picture below.

The molecule you just build was a covalently bonded water molecule. The chemical equation for a water molecule is H2O. Covalently bonded H2O molecules share electrons; in other words, in a water molecule, electrons are shared between the hydrogen atoms and oxygen atom. In this picture, the yellow gumdrops represent hydrogen atoms, the pink gumdrop represents an oxygen atom, and the toothpicks represent covalent bonds.

5) After you have assembled the covalently bonded water molecule, assemble one gumdrop from each of the remaining two colors of gumdrop piles and one toothpick from the remaining toothpicks to look like the picture below.

The molecule you just built was a molecule of sodium chloride salt. The chemical equation for sodium chloride is NaCl. NaCl is bonded by ionic bonds. To create the ionic bond, the chlorine atom takes an electron from sodium. As a result, sodium becomes a positively charged ion and chlorine becomes a negatively charged ion. In this picture, the green gumdrop represents a chlorine atom, the orange gumdrop represents a sodium atom, and the toothpick represent an ionic bond.

6) Following this, assemble the remaining gumdrops like the picture above into more sodium chloride molecules. After doing so, you should have a few remaining toothpicks. Use said toothpicks to create the cube-like structure of bonded sodium chloride (NaCl) pictured below.


Due the fact that the sodium and the chlorine in the sodium chloride salt become charged ions, they attract other sodium and chlorine ions to form an intricate structure like the one modeled below.

7) Finally, using your creations, answer the comprehension questions.


1) What characterizes an ionic bond? Are ions good at sharing electrons?

2) What characterizes a covalent bond? Are covalently bonded atoms good at sharing electrons?

3) What is another example of an ionic molecule? What is another example of a covalently bonded molecule? (If you cannot answer this question, you may do an Internet search with your instructor’s permission.)


How Many Drops?


There are two types of molecular interaction: intramolecular bonds and intermolecular forces. This experiment illustrates intermolecular forces.

Intermolecular forces act between molecules and affect physical properties of the substance such as surface tension, boiling point, and viscosity. Different types of intermolecular forces include hydrogen bonds, London dispersion forces, and dipole-dipole forces.

Definitions:


Intermolecular forces: This is a type of bonding that occurs between molecules. Hydrogen bonds: A type of intermolecular bonding where a hydrogen atom that is part of

a larger molecule, such as H2O (water), becomes momentarily positive and is attracted to another very negative atom on another molecule, such as oxygen on another H2O molecule.

Materials List:

Penny

Dropper (pipettes would be preferable)

Cup of water

Paper or plastic plate

Paper towels

Notepad

Colored pens and/or pencils (to draw and to record data)


Procedure:

1) Lay out all the materials you need to conduct this experiment on a countertop in front of you. (Your items may vary from the ones found below.)

2) Fill the pipette/dropper with water.


3) Place the penny on the plate and slowly, counting each drop, drop droplets of water onto the surface of the penny until the droplet breaks and spills over onto the plate. The picture below illustrates what a penny with a broken water droplet looks like.

4) Remember the number of drops it took before you made the droplet break and record that number in the table. This value can be found by subtracting one drop from the total number of drops you dropped onto the penny before the water droplet spilled over the side of the penny.

5) Dry off the penny and the plate with the paper towel, and, then, repeat the experiment. This time drop water onto the penny and stop before the water droplet spills off the surface of the penny.

6) Next, get eye level to the surface of your penny. Once you are at eye level, draw a picture of your penny with the droplet of water on it below. The penny you draw should look something like the one in the picture below. Specifically, you penny should also have a rounded water droplet on top.


7) Once you have completed your drawing, answer the comprehension questions below.

Data Chart:

Material Number of drops (before the water droplet broke)

Penny

Drawing:



In this experiment, you observed the result of one of chemistry’s most important intermolecular forces: hydrogen bonds. As you were dropping more and more drops of water onto the surface of the penny, you should have noticed the water made a dome shape on top of the penny. This dome shape is the result of the surface tension caused by the hydrogen bonds. Aren’t bonds interesting?

1) When the water droplet broke was the change sudden or did the water leak off slowly? Why do you think the water droplet broke? Were the hydrogen bonds strong enough to keep the water droplet together?

2) What other liquids could you use to test their surface tension? Go ahead and test one other liquid. What did you find? Did it behave like water did in the experiment?

3) Do you think this experiment would work better if you used a material with even stronger intermolecular forces? Would stronger intermolecular forces permit more drops of liquids to accumulate on the surface of the penny?


What are the States of Matter?


There are three main observable states of matter in the universe: solids, liquids, and gasses. Solids have atoms that are essentially locked in position and are unable to move very readily. Solids have a definite volume and shape and do not compress easily (“States of Matter”). Examples of solids include ice, glass, aluminum foil, salt, and sugar.

Liquids have atoms/molecules that are not locked into position and have more freeform movement. Liquids maintain the shape of their containers and flow easily; however, like solids, liquids are not easily compressible and do have a definite volume (“States of Matter”). Examples of liquids include water, ammonia, isopropyl alcohol, and milk.

Gasses have atoms/molecules are able to move past one another very readily, even more readily than in liquids. Gasses do not have a definite volume or definite shape and are extremely compressible (“States of Matter”). Examples of gasses include water vapor (H2O), carbon monoxide (CO), carbon dioxide, (CO2), and oxygen (O2).

When heated, a solid melts and turns into a liquid. Then, the liquid can vaporize into a gas. Eventually, the gas can condense into liquid once again. Finally, the liquid can freeze back into a solid.

Definitions:

Atom: The most basic, fundamental component of matter. Molecule: This is a substance that forms from the combination of two or more atoms. Solid: A state of matter in which atoms or molecules are arranged in a definite structure. Liquid: A state of matter in which atoms or molecules are able to move around more

readily than in solids. Gas: A state of matter in which atoms or molecules have no definite structure. In this

state of matter, atoms and molecules are able to move even more readily than in liquids. Vaporize: The process during which a liquid turns into a gas. Condense: A process during which a gas turns back into a liquid.

Materials List:

One see-through, clear plastic or glass container with a lid

Ice cubes (four)

Sunny windowsill or countertop

Towel

Stopwatch to keep track of hours (or watch that can function as a stopwatch)


Procedure:

1) First, lay out all the necessary materials. (Your items may vary from the ones found below.)

2) Next, after making sure the lid is off of the container, place the four ice cubes into the jar and secure the lid onto the container.


3) After you have placed the ice cubes in the jar and closed it, place the container in the sun on a windowsill or counter top. To make sure the water doesn’t melt everywhere, place a towel underneath the container.


4) For about an hour or two, check on the ice cubes every fifteen minutes until they have melted. Once they have melted, record the time it took to melt in the data chart. You just witnessed a solid turn into a liquid!

5) Now, wait another hour or until you see droplets of water form on the top of the lid or the sides of the container. In order not to miss anything, check the jar every fifteen minutes. After the droplets have formed, record the time it took for this to occur in the data chart.


6) Using your data and understanding of the states of matter, answer the comprehension questions.

Data Record Chart:

State of matter Time it took for that state of matter to appear

Ice (solid)

Water (liquid)

Water droplet(s) (which is a liquid and also the condensed form of water vapor)


In this experiment, you watched as solid water melted into liquid water and as liquid water evaporated into a gas and condensed on the lid or sides of your container. Although you couldn’t see the water vapor, since it was clear, you were able to see the result of evaporation and condensation! Aren’t the states of matter interesting!

1) When you placed the ice cubes in the container, did they stay the same shape? Or did they conform to the size and shape of the container? (Hint: Do solids have definite shapes and volumes, or do their shapes and volumes change depending upon the container?)


2) Once the ice cubes had melted, did the water stay in the same shape as the shape the ice cubes? Or, did the liquid conform to the shape of the container? (Hint: Do liquids have definite shapes and volumes, or do their shapes and volumes change depending upon the container?)

3) If you could see the water vapor molecules, do you think they would stay in the same shape as the ice cubes? Or, do you think they would take the shape of the container?(Hint: Do gasses have definite shapes and volumes, or do their shapes and volumes change depending upon the container?)

4) What other examples of solids, liquids, and gasses can you list? (If you cannot think of another example of each, feel free to do an Internet search with your instructor's permission.)


Chemical Reactions: Hot vs. Cold



Chemical reactions occur when either atoms or molecules of a reactant, the starting substance, collide and form products, the substance you get at the end of a chemical reaction.

In order to form the product, the reactants must collide with one another.

When you crack a glow stick, you release a liquid that was previously trapped in a tube and allow it to combine with another liquid.

These two liquid reactants give off light when they react to form a product. The fact that light emits from the glow stick lets you know a chemical reaction is occurring.

Each of the reactant atoms or molecules has kinetic energy, which is the energy of movement.

When you measure the temperature of something, you are measuring the average kinetic energy of the molecules or atoms.

With this information, what do you think will happen when you raise the temperature of a chemical reaction?

Definitions:

Atom: The most basic, fundamental component of matter. Molecule: A substance that forms from the combination of two or more atoms. Chemical Reaction: The process of changing some element or elements into another

form. Reactant: The chemical elements, molecules, or substances that are used in the beginning

of an experiment. Product: The chemical molecules or substances that result from a chemical reaction. Kinetic Energy: The name for the energy of motion.

Materials List:

Glow sticks (three of the same color)

Room temperature water (approximately six cups)

Kettle in which to boil water

One-cup measure


Thermometer

Ice cubes (six)

Coffee mugs (three)

Stopwatch or clock (to keep track of time)


An adult to help with step three

Procedure:

1) First, collect and lay out all of the required materials. (Your items may vary from the ones found below.)

2) After you have done this, boil about three cups of water.


3) Following this, use the measuring cup to pour one cup of the boiling hot water into one of the coffee mugs. In this step, please ask an adult for assistance in pouring the boiling hot water, so you do not get burned.

4) After this, fill the second coffee mug with one cup of room temperature water.

5) Finally, fill the third coffee mug with one cup of room temperature water and add the six ice cubes to the water.


6) Next, crack the three of the glow sticks and insert one glow stick into each mug.

7) Now, record the temperature in degrees Fahrenheit of the water in each of the three mugs.

8) Finally, record your color observations for the glow sticks and answer the comprehension questions.

Data Chart:

Glow stick in hot water

Glow stick in room-temperature water

Glow stick in cold water

Temperature of water (˚F)

Color observations


1) Was there a color difference between the glow sticks when you looked at how they glowed in the cups? If so, which glow stick was most vibrant? Which was the least?

2) What effect would you say the thermal energy (heat energy) had on the glow sticks?

3) On a molecular level, which reactant molecules, the colder ones or the hotter ones, were moving the fastest? Which were moving the slowest?

4) What do you think would happen if you lowered the temperature of another chemical reaction such as a baking soda and vinegar reaction? What if you raised the temperature of the baking soda and vinegar reaction?


Reactions that are Hot?


Chemical reactions occur when either atoms or molecules of a reactant, the starting substance collide and form products, the substance you get at the end of a chemical reaction.

One way in which to know a chemical reaction is occurring is that the reaction gives off heat.

In this instance, when the reactants collide to form products, energy is released as heat energy. This type of reaction is called an exothermic chemical reaction. (If you remember, in an earlier reaction, energy was given off in the form of light.)

With this information, what do you think is happening inside of a hand warmer? Is this an example of an exothermic chemical reaction?

Definitions:

Chemical Reaction: The process of changing some element or elements into another form.

Atom: The most basic, fundamental component of matter. Molecule: This is a substance that forms from the combination of two or more atoms. Reactant: The chemical elements, molecules, or substances that are used in the beginning

of an experiment. Product: The chemical molecules or substances that result from a chemical reaction. Exothermic Chemical Reaction: This is a type chemical reaction that gives off energy in

the form of heat.

Materials List:

Air-activated hand warmer

Stopwatch (or watch that can function as a stopwatch)



Procedure:

1) Lay out all of the required materials. (Your items may vary from the ones found below.)

2) Next, open the hand warmer and take it out of any packaging.

3) Once you have removed the hand warmer from any packaging, shake the hand warmer vigorously in order to mix the inner contents.

4) Start the stopwatch.


5) In the table below, record your observations about the initial temperature of the hand warmer.

6) After ten minutes, record new information about the temperature. Include information such as “it has gotten hotter,” “it is now lukewarm,” and/or “the temperature has increased.” Please note you do not have to fill out the actual temperature value. Rather, all you have to do is record an observation similar to the ones previously listed.

7) Following another ten-minute interval, or twenty minutes total, record your observations.

8) Finally, after another ten minutes, or thirty minutes total, record your final observations.

9) Using your information, answer the comprehension questions.

Data Chart:

Hand warmer

Initial observations of temperature

Observations of temperature increase after 10 minutesObservations of temperature increase after 10 more minutes, or 20 minutes totalObservations of temperature increase after 10 more minutes, or 30 minutes total



1) What do you think caused this reaction to begin? To what extent do you think air might have had something to do with it?

2) What other examples of exothermic chemical reactions can you think of that occur around you? (If you cannot think of any examples, you may do a quick Internet search with your instructor’s permission.)

3) Do you think that there are reactions that absorb heat, too? What do you think those types of reactions would be called? (Hint: endo- is a prefix that means within, whereas exo- is a prefix that means external.)


Reactions that are Cold?



One way in which to know a chemical reaction is occurring is that a temperature change occurs. This temperature change can occur in the form of a temperature increase of the chemical reaction or a temperature decrease of the chemical reaction.

In this instance, when the reactants collide to form products, energy is absorbed, so the reaction is cold to the touch. This type of reaction is called an endothermic chemical reaction. (If you remember, in earlier reactions, energy was given off both as light and as heat.)

With this information, what do you think is happening inside of a hand warmer? Is this an example of an endothermic chemical reaction?

Definitions:



of an experiment. Product: The chemical molecules or substances that result from a chemical reaction. Endothermic Chemical Reaction: This is a type chemical reaction that absorbs energy and

is, as a result, cold to the touch.

Materials List:

Instant ice pack (one that requires you to release an inner liquid pouch to get cold)




Procedure:

1) Lay out all of the required materials. (Your items may vary from the ones found below.)

2) Next, remove the ice pack from any packaging.


3) After removing the ice pack from any packaging, follow the instruction to break the sealed inner liquid.

4) Once you have released the inner liquid, shake the ice pack vigorously to mix the inner contents.

5) Start the stopwatch.

6) Record observations about the initial temperature of the ice pack in the table by touching it with your hand to feel how cold it either is or is not.

7) After ten minutes, record new information about the temperature by again touching the ice pack to see how cold it either is or is not. Include information such as “it has gotten colder,” “it is now freezing,” and/or “the temperature has decreased.” Please note you do not have to fill out the actual temperature value. Rather, all you have to do is record an observation similar to the ones previously listed.

8) Following another ten-minute interval, record additional observations. You should again use a touch-test method to see how cold the ice pack either is or is not at this point in the experiment.

9) Finally, after another ten minutes, or thirty minutes total, record your final observations about the ice pack using the touch method.


10) Using your information, answer the comprehension questions.

Data Chart:

Ice pack

Initial observations of temperature

Observations of temperature decrease after 10 minutesObservations of temperature decrease after 10 more minutes, or 20 minutes totalObservations of temperature decrease after 10 more minutes, or 30 minutes total


1) What do you think were the reactants in this reaction? How do you think the reaction was activated?

2) What other examples of endothermic chemical reactions can you think of that occur around you or are useful to you? (If you cannot think of any examples, you may do a quick Internet search with your instructor’s permission.)

3) What do you think are other indicators of chemical reactions? You have already seen chemical reactions that are indicated by temperature change and the release of heat. (If you cannot think of any examples, you may do a quick Internet search with your instructor’s permission.)


Let’s Test for Starch!



Chemical reactions are used in both useful and educational manners. Most importantly, chemical reactions are fun to watch, participate in, and study!

One of the most enjoyable, and “fun,” experiments to watch is the chemical reaction that occurs between iodine and plant starch. Plant starch, which is made up of a type of plant sugar called glucose, can be separated into two components: amylose and amylopectin (“Starch and Iodine”).

Iodine, which is a chemical element on the periodic table, reacts when in the presence of the plant starch component amylose (“Starch and Iodine”). This amylose is what causes the iodine to turn a vibrant color. As a result, scientists use iodine as an indicator for plant starch and so can we!

What color do you think iodine turns in the presence of starch? Don't you want to find out?

Definitions:



of an experiment. Iodine: A chemical element that changes color in the presence of amylose. Amylose: A chemical component of plant starch that causes iodine to change color due to

a chemical reaction between the iodine and the amylose.

Materials List:

Liquid iodine solution (this can be found at a local drug store)

Permanent marker

Styrofoam or plastic disposable plates

Apron

Plastic tablecloth or covering (paper towels can work)



Ruler or tape measure (that measures mm)

Dropper or pipette

Paper

Potato slice (thin slice)

Carrot (thin slice)

Paper towel or napkin (to wipe up potential spills)

Penny

Soda cap (or other plastic object)

Knife

An adult to help with step three

Procedure:

1) Collect and lay out all necessary materials on an easily cleanable countertop. Since iodine stains clothes and countertops very easily, be sure to put on an apron and cover your workspace with a plastic tablecloth or another form of protective covering. (Your items may vary from the ones found below.)


2) If you need to, slice the potato and the carrot now with an adult's help. You should have a 2-3 mm thick slice of each before you move onto step three.

3) Take the stack of plastic or Styrofoam plates and, using the permanent marker, label each plate with the name of the item you will test on that plate.

4) Place each test item on its respective labeled plate.


5) Taking the first plate, open the bottle of iodine solution and use the dropper to drop about four drops of iodine onto the test item. When you are using the iodine, remember to be very careful, because iodine stains clothing and countertops very easily.

6) Following this, record any color changes or observations. If the test item contains starch, the color of the iodine will darken like in the photograph below. If the test item does not contain starch, the iodine solution will simply stay the same color as it was originally.


7) Finally, repeat steps four and five until you have tested each of the items.

8) After this, conclude whether or not each item contains starch and write your conclusion in the data chart. (Note again that if the iodine changes color after it is dropped onto the test object, there is starch present.)

9) Using the information you recorded in the data table, answer the comprehension questions.

Data Chart:

Test item Color change? (If yes, what color?)

Starch present?

Paper

Potato

Carrot

Penny

Soda cap



In this experiment, you used the chemical element iodine to test different household items to see if they contained starch. As you now know, the chemical reaction that occurs between iodine and starch creates a vibrant color change. Isn’t chemistry interesting!

1) In the items where starch was present, what color change occurred in the iodine? Was the color change immediate, or did it take a long time to occur?

2) Of the test items, which contained starch? Which did not contain starch? How could you tell whether or not the items contained starch?

3) How could you tell a chemical reaction occurred between iodine and starch? Do you think one of the indicators of a chemical reaction is a color change? Why?

4) If there were no color change, did a chemical reaction still occur? (Hint: If you cannot answer this question, think back to how you know a chemical reaction occurred between the iodine and the starch.)


Let’s Blow up a Balloon!



By definition, matter undergoes certain changes during a chemical reaction that can result in structure reorganization and/or transfer of electrons. These changes can be illustrated by changing temperatures, light emissions, and/or transformations between states of matter.

For example, when a change in matter occurs, you can start with two liquid reactants and end up with a liquid product and a solid precipitate. Or, you can watch a chemical reaction that has a solid reactant and a liquid reactant that results in a liquid product and a gaseous product.

How do you think you can apply these ideas to blow up a balloon via a chemical reaction?

Definitions:


Atom: The most basic, fundamental component of matter. Electron: The negatively charged part of an atom. Molecule: This is a substance that forms from the combination of two or more atoms. Reactant: The chemical elements, molecules, or substances that are used in the beginning

of an experiment. Product: The chemical molecules or substances that result from a chemical reaction. States of Matter: Three states of matter are solids, liquids, and gasses. Precipitate: Another name for the solid product that may result from a chemical reaction.

Materials List:

Teaspoon measure

Measuring cup that measures ½ cup

Bottle of white vinegar (enough for ½ cup)

Empty plastic container (be sure to wash the inside out, so the container is clean)

Rubber balloon (have two on hand, just in case one of them breaks)

Baking soda (enough for two teaspoons)

Piece of paper (to use as a funnel to transfer the baking soda into the balloon)



Tape


Another person (if you need help with step five of the experiment)

Procedure:

1) Lay out all the necessary materials out on an easily cleanable countertop. (Your items may vary from the ones found below.)

2) After you have completed step one, curl the paper into a funnel and place a piece of tape on the side to secure the funnel. If you need help, see the photo below.


3) Place the bottom of the paper funnel into the mouth of the balloon and, using the tablespoon measure, measure and pour two teaspoons of baking soda into the funnel. If you need to, tap the funnel or flick the side of the funnel with your finger to make sure all the baking soda gets into the body of the balloon.

4) Next, using the measuring cup, pour about ½ a cup of white vinegar into the empty, rinsed bottle.


5) After you have poured ½ a cup of white vinegar into the plastic bottle, have someone hold the now filled bottle while you place the bottom of the balloon around the top of the plastic bottle. While you are doing this, be careful to not let any of the baking soda empty into the vinegar.

6) Before you empty the balloon into the vinegar, record your initial observations of the chemical reaction in the data chart.

7) First, empty the balloon into the vinegar and start the stopwatch. Then, record additional observations of what takes place during the chemical reaction.

8) Watch the reaction until it stops and record the time information and your observations.

9) Finally, answer the comprehension questions using the information you wrote in your data chart.


Data Chart:

Step of the chemical reaction ObservationsBefore emptying the balloon

How long did it take for the chemical reaction to start?

After emptying the balloon

How long did it take for the chemical reaction to stop?

After the chemical reaction stopped


In this chemical reaction, you saw matter undergo a transformation, as a result of the chemical reaction. Specifically, you witnessed a chemical reaction where one of the reactants did not retain its original state of matter. While not all chemical reactions occur in this manner, all chemical reactions change matter in some way, shape, or form.

1) What change of state did you witness? What original reactants did you have? What were their states of matter? What were the final states of matter of the products?(Hint: How do you think the balloon filled up?)

2) Using what you have learned about chemical reactions, how do you think we know a chemical reaction occurred when you emptied the balloon into the bottle? What kind of observable changes did you notice? (Hint: Did bubbles appear? Did the balloon fill up with a gas? Was a gas one of the original reactants?)

3) What is the balanced chemical equation for the experiment you just saw? In the balanced chemical equation, what states of matter do they denote for the products?(To help answer this question, you may do an Internet search with your instructor’s permission. I would recommend searching something along the lines of “baking soda and vinegar chemical reaction equation with states of matter.”)


How Does Surface Area Affect A Reaction?



Chemical reactions occur when either atoms or molecules of a reactant, the starting substance, collide and form products, the substance you get at the end of a chemical reaction.

In order to form the product, the reactants must be able to collide with one another.

When you have a chemical reaction that has at least one reactant that is in the form of a solid, you can say the solid reactant has a surface area.

What do you think will happen when more of a reactant solid’s surface area is exposed and available to engage with another reactant, or multiple reactants, in a chemical reaction?

Definitions:

Atom: The most basic, fundamental component of matter. Molecule: A substance that forms from the combination of two or more atoms. Chemical Reaction: The process of changing some element or elements into another

form. Reactant: The chemical elements, molecules, or substances that are used in the beginning

of an experiment. Product: The chemical molecules or substances that result from a chemical reaction. Surface Area: The amount of a solid’s surface that is exposed.

Materials List:

Four Alka-Seltzer tablets

Metal spoon

Hard surface

Four clear plastic cups

Pitcher of room temperature water

Measuring cup (one-cup measure)


Thermometer

Permanent marker Pen (to record data)


Procedure:

1) First, collect and lay out all the required materials on a table or countertop. (Your items may vary from the ones found below.)

2) Next, take the temperature of the water and record the information in the data chart found below.

3) Now, tear the wrapper off of the four Alka-Seltzer tablets and lay the tablets in front of you.

4) In these next two steps, you will increase the surface area of three of the tablets. Break the


first tablet into two large pieces. Break the second tablet into multiple tiny pieces.

5) Using the metal spoon, crush the third tablet into powder. Finally, leave the fourth tablet in one whole piece.

6) Next, label each of the cups. The first cup should say “whole tablet.” The second cup should say “tablet halves.” The third cup should say “tablet pieces.” Finally, the fourth cup should say “tablet powder.”


7) Now, you will distribute the tablets/pieces of tablets. Place the whole tablet into its cup.

8) Then, place the tablet halves into the correct cup.

9) Next, place the crushed tablet into its cup.

10) Finally, put all of the powder from the powdered Alka-Seltzer tablet into its cup.

11) Following this, use the measuring cup and measure one-cup of room temperature water into each of the four clear, labeled plastic cups.

12) Start the stopwatch as soon as you have finished pouring water into the cups.

13) Watch the reactions and record your observations in the table about the reaction that appears to be occurring most quickly. (You will know that the reaction is taking place, because there will be bubbles forming in the water just like in the photograph below.)


14) As soon as the first reaction is done, record the time. Follow this same procedure and record the time each subsequent reaction finishes. (You will know when the reaction stops, because the water virtually stops fizzing just like in the photograph below.)

15) Now, using your data, answer the comprehension questions.


Data Chart:

Alka-Seltzer reaction

Initial temperature of water (˚F)

Observations of chemical reaction occurring at the beginning (Record the speed at which bubbles rise to the surface)Record of how much time it took for the reactions to end


In this experiment, you changed the surface area of Alka-Seltzer tablets and observed how the increased surface area affected the reaction between the Alka-Seltzer tablets and water. The tablet that you crushed into powder had the largest surface area. The whole tablet had the smallest surface area.

1) Which tablet reacted most quickly? How would you describe the surface area of this tablet?

2) Which tablet reacted least quickly? How would you describe the surface area of this tablet?

3) How would you speed up another reaction between a solid and a liquid? Which do you think would make the reaction go more quickly? Increasing or decreasing the surface area?


Glossary:

Amylose: A chemical component of plant starch that causes iodine to change color due to a chemical reaction.

Atom: The most basic, fundamental component of matter.


Condense: A process during which a gas turns back into a liquid.

Covalent bonds: A type of intramolecular bond in which atoms share electrons between one another.

Electron: The negatively charged part of an atom.

Endothermic Chemical Reaction: This is a type chemical reaction that absorbs energy and is, as a result, cold to the touch.

Exothermic Chemical Reaction: This is a type chemical reaction that gives off energy in the form of heat.

Gas: A state of matter in which atoms or molecules have no definite structure. In this state of matter, atoms and molecules are able to move even more readily than in liquids.

Hydrogen bonds: A type of intermolecular bonding where a hydrogen atom that is part of a larger molecule, such as H2O (water), becomes momentarily positive and is attracted to another very negative atom on another molecule, such as oxygen on another H2O molecule.


Intermolecular forces: This is a type of bonding that occurs between molecules.

Iodine: A chemical element that changes color in the presence of amylose (if needed, see definition for “amylose” above).

Ion: An either positively or negatively charged particle.

Ionic bonds: A type of intramolecular bond in which one atom transfers electrons to another atom.

Kinetic Energy: The name for the energy of motion.

Liquid: A state of matter in which atoms or molecules are able to move around more readily than in solids.


Molecule: A substance that forms from the combination of two or more atoms. Neutron: The uncharged, or neutrally charged, part of an atom.

Nucleus: The central part of an atom that is made up of both protons and neutrons.

Orbital: A way of drawing the energy level(s) at which an atom’s electrons exist.

Precipitate: Another name for the solid product that may result from a chemical reaction.

Product: The chemical molecules or substances that result from a chemical reaction.

Proton: The positively charged part of an atom.

Reactant: The chemical elements, molecules, or substances that are used in the beginning of an experiment.

Solid: A state of matter in which atoms or molecules are arranged in a definite structure.

States of Matter: Three states of matter are solids, liquids, and gasses.

Surface Area: The amount of a solid’s surface that is exposed.

Vaporize: The process during which a liquid turns into a gas.


Bibliography:

"AP Chemistry Course and Exam Description." (n.d.): n. pag. The College Board, 2014. Web. 12 June 2015.

Bradford, Alina. "Science & the Scientific Method: A Definition." LiveScience. TechMedia Network, 30 Mar. 2015. Web. 25 July 2015.

"Chemistry Dictionary, Terms & Definitions - Chemistry-Dictionary.com." ChemistryDictionarycom. N.p., n.d. Web. 12 June 2015.

Dictionary.com. Dictionary.com, n.d. Web. 12 June 2015.

"General Chemistry Online: Companion Notes: Chemical Change: 10 Signs of Change." General Chemistry Online: Companion Notes: Chemical Change: 10 Signs of Change. N.p., n.d. Web. 12 June 2015.

GS_gold_pin. Digital image. Highest Awards in Girl Scouting. Girl Scouts of Greater Iowa, n.d. Web. 12 June 2015.

Helmenstine, Ph.D. Anne Marie. "Home Chemistry Kit - Projects & Experiments." N.p., n.d. Web. 12 June 2015.

Helmenstine, Ph.D. Anne Marie. "Homeschool Chemistry." N.p., n.d. Web. 12 June 2015.

"How Should the Reaction between Vinegar and Baking Soda Be Classified?" General Chemistry Online: FAQ: Chemical Change:. N.p., n.d. Web. 14 Aug. 2015.

"Hydrogen Bonding." Chemwiki. University of California, Davis, n.d. Web. 12 June 2015.

"Inly School." Elementary School Students. N.p., n.d. Web. 12 June 2015.

"Intermolecular Forces." Intermolecular Forces. N.p., n.d. Web. 12 June 2015.

"Intermolecular Forces." (n.d.): n. pag. Web. 12 June 2015.

"Liquids, Solids, Intermolecular Forces." Liquids, Solids, Intermolecular Forces. N.p., n.d. Web. 12 June 2015.

"Neutron Madness." Chem4Kids.com: Atoms: Isotopes. N.p., n.d. Web. 12 June 2015.

"NSTA Position Statement." Elementary School Science. National Science Teachers Association, July 2002. Web. 11 June 2015.

"Parts of Your Self-Published Book." Parts of a Book. N.p., n.d. Web. 12 June 2015.


"Physical and Chemical Properties." Physical and Chemical Properties. N.p., n.d. Web. 12 June 2015.

"Starch and Iodine." - Chemwiki. University of California, Davis, n.d. Web. 12 June 2015.

"States of Matter." States of Matter. Purdue University, n.d. Web. 12 June 2015.

"Steps of the Scientific Method." Steps of the Scientific Method. N.p., n.d. Web. 25 July 2015.

"The Scientific Method." Science Bob. Science Bob, n.d. Web. 25 July 2015.

"Teaching Resources." Teaching Resources. UC Berkeley, n.d. Web. 11 June 2015.

"WebElements Periodic Table: The Periodic Table on the Web." WebElements Periodic Table of the Elements. N.p., n.d. Web. 12 June 2015.


chemistry booklet final (august 21).docx

Documents

cold pages

scientific experiment

bibliography pages

glossary pages

scientific process

covalent bonds pages

scientific language

background information