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Science curriculum for K—5th grades.

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Chemical Magic

Chemical Reactions & Properties of Matter

4th Grade, 5th Grade

NGSS Standards covered: 5-PS1-4 , 5-PS1-1 , 5-PS1-3 , 5-PS1-2
This unit helps students develop the concepts of “substances” and “chemical reactions.” Students see that chemical reactions enable us to make new materials by transforming the ones we have. The results of these reactions are interesting and sometimes profoundly useful. Less
  1. Lessons
  2. Activity Prep
  3. Assessments

Mystery 1: Introduction to Chemistry

Test Like An Alchemist

In this Mystery, students meet the alchemists, a historic group that used “potions” to try to transform materials. In the activity, students test what substances change the appearance of copper. In this activity, students test liquids to see which ones will clean the tarnish off a penny. Then, when one penny changes from dark and dirty to bright and shiny, they’ll have a chance to think about where the tarnish went.

LESSON REVISED 1/11/18. If you prepped before then, use the previous version.

Number of students:
Clean-up Supplies (Ex. Paper Towels)
1 roll. In case of spills.
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Tape
1 roll
Liquid soap
2 tablespoons. Can also use liquid detergent.
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Measuring Cup
1 cup
Measuring Spoons
1 set
Plastic Containers w/ Lids
4 containers. Each container needs to hold just over 3 cups.
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Salt
1 cup. You’ll need another cup of salt for Mystery 3, so we suggest getting a 26 oz container.
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White Vinegar
4 cups. You will also need vinegar for other lessons in this unit, so we suggest getting a gallon.
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Pennies (must be pre-1982)
30 coins. Each student needs one penny, but if you're working in a small group you need a minimum of 20. We suggest having a few extra in case some get lost.
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Steel Nails
1 nail. It’s important that you get steel nails (or steel washers)—NOT stainless-steel and NOT galvanized steel. For Mystery 2, each group of 4 students will also need one nail. Jumbo paper clips will also work, but the results are harder to see.
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Alchemist’s Potion, Part 1 printout Print 30 copies
Container Labels printout Print 1 copy
Test Like An Alchemist printout Print 8 copies

OPTIONAL SUPPLIES

Crayons
16 crayons. Orange and brown for coloring dull and shiny pennies on worksheets. Colored pencils will also work.
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Prep Instructions

We recommend students work in groups of four. Homeschool students can work on their own.

You will need access to water for this activity.

You will need old, tarnished pennies for this activity. You must use pennies dating from BEFORE 1982, when they were made from 95% copper. (Pennies made after 1982 are copper-plated zinc, which won’t work for this activity.)

We suggest asking students to bring in pennies made before 1982. You can also buy penny rolls at the bank. We bought $3 worth, sorted out the pre-1982 pennies, and had exactly 40 to work with. If you are working with a homeschool student or small group, you’ll need a minimum of 20 pennies

In the next Mystery, you’ll need to reuse some of the materials from this Mystery so students can copper plate a steel nail. See instructions below.

Prepare Your Testing Liquids

Cut out the Container Labels and tape one to each of your four plastic containers. You now need to prepare 2 cups of each testing solution. If you’re working with a homeschool student or small group, you can make 1 cup of each solution, rather than 2. When you set up your stations, just cut the following “recipes” in half.

  • Soapy Water Station: Mix 2 tablespoons liquid soap (or detergent) with 2 cups water.
  • Vinegar Station: Pour 2 cups of vinegar.
  • Salt and Vinegar Station: Mix 6 tablespoons salt with 2 cups vinegar. The salt won't all dissolve, but add it anyway.
  • Salty Water Station: Mix 6 tablespoons salt with 2 cups water. The salt won't all dissolve, but add it anyway.

We recommend placing each container in a separate area of the classroom as a test station.

Save Materials and Prepare for the Next Mystery

  • Save student work: Students will need their completed “Alchemist’s Potion, Part 1” printouts for the next Mystery. Make sure they’re stored somewhere safe.

  • Save the pennies in the Salty Vinegar solution: At the end of this Mystery, you’ll dump all the pennies into the Salty Vinegar to soak overnight. (If you made just 1 cup of Salty Vinegar, dump at least 20 pennies into it.)

  • Add a nail: After students have left class, we recommend that you put a nail into the Salty Vinegar solution with the pennies — but don’t tell your students you’re doing it. You’ll find out why in the next Mystery, when your students will discover that the solution the pennies soaked in can change steel in a surprising way.

Mystery 2: Particulate Nature of Matter

The King's Sword

In this Mystery, students investigate the alchemists’ claim of transforming ordinary metals into gold. In the activity, students coat a steel nail with copper and develop a particle model to explain what they observe. In this activity, students use the vinegar, salt, and penny solution that they created in Mystery 1 to copper plate a steel nail. Students then create a conceptual model of how particles from the pennies are the same ones that eventually coat the nail in copper.

THIS LESSON WAS REVISED ON JANUARY 11, 2018. If you've prepped prior to that date, we suggest using the previous version.

Number of students:
Alchemist's Potion printouts from Chemical Magic Mystery 1
30 printouts. Completed in the previous lesson.
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Clean-up Supplies (Ex. Paper Towels)
1 roll. In case of spills.
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Vinegar & Salt Solution from Chemical Magic Mystery 1
1 container. Filled with pennies and a steel nail.
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Dixie Cups (3 oz)
8 cups
Medium Binder Clips (1 1/4")
8 clips. Used to clip Ziploc bags to the plastic bin. Clothespins or masking tape can also work.
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Paper Plates (9")
8 plates. Plastic plates will also work.
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Plastic Bin
1 bin. Used to store Ziploc bags for students. Bin must be large enough so that all groups of students can clip their bag to the sides of the bin (8 Ziploc bags for a class of 32).
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Plastic Spoons
4 spoons
Sticker Labels (1" x 3")
16 labels. Masking tape will also work.
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Ziploc Bags (Sandwich Size)
8 bags. Ziploc snack size bags also work.
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Steel Nails
8 nails. It’s important that you get steel nails (or steel washers)—NOT stainless-steel and NOT galvanized steel. Jumbo paper clips will also work, but the results are harder to see.
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Alchemist’s Potion, Part 2 printout Print 30 copies

OPTIONAL SUPPLIES

Crayons
60 crayons. Orange and brown. Colored pencils also work.
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Prep Instructions

To do this activity, you must have completed the activity in Mystery 1.

We suggest students work in groups of four. Homeschool students can work on their own, but will need help with some steps.

Remove the Steel Nail from the Vinegar and Salt Solution

At the end of the last Mystery, you put all the pennies in the vinegar and salt solution, added a steel nail when students were gone, and then left the solution overnight. To prepare for this activity, check on that solution before class and look at the nail you put in. All or part of the nail should now be covered by a layer of copper.

Take the nail out of the solution, rinse it off, and set it aside to show your students during the last video. Save the penny-filled solution for students to use in this activity.

Prepare Materials for Classroom Distribution

Students will first need the following materials:

King

We then recommend you set up three stations around the classroom:

  • Potion Pro & Penny Pro Station: Pennies in the vinegar and salt solution along with the spoons for scooping up pennies and one Dixie cup for each group
  • Bag Boss Station: A Ziploc bag for each group
  • Steel Master Station: A steel nail for each group

King

Have a Plastic Bin Ready to Store Student Experiments

If conditions are just right, copper forms on the steel quickly. But in many cases, students may need to leave their experiments for a few hours or even overnight to see results.

To store students' experiments overnight, we suggest clipping the Ziploc bags to the sides of a plastic bin, with the bags hanging over the inside of the bin. This ensures that the nail remains submerged in the liquid. In the unlikely event that the bags leak, the bin will catch the vinegar.

Mystery 3: Acids, Reactions, & Properties of Matter

Acid Test

In this Mystery, students are introduced to acids, a group of substances with a reputation for being reactive. In the activity, students develop their own test for acids, then apply it to several common household substances in order to identify which contain acids.

THIS LESSON WAS REVISED ON JANUARY 11, 2018. If you've prepped prior to that date, we suggest using the previous version.

In this activity, students discover two ways to detect acids. Then they test condiments and other foods to figure out which ones are acids.

Step 1: Think ahead

For a class or large group, we suggest students work in groups of four at a workstation where they can share supplies. Within each group, students will work with a partner. Students working at home can work on their own or with a partner.

Before buying supplies, figure out how many groups you’ll have, so you can set up supplies accordingly.

Step 2: Gather equipment and supplies

To prepare for class, you’ll need:

  • measuring spoons and cups
  • scissors
  • a sharpie or permanent marker
  • 1 cup of dry black beans or 2 cups of chopped raw purple cabbage
  • 2 cups of water
  • a container that can hold at least 4 cups of water (for making purple indicator liquid; see Step 4 for instructions)
  • 20 drinking straws (you’ll be modifying these so students can use them for transferring liquids; see Step 4 for instructions)
  • at least two foods or drinks that students can test for acidity (Anything in the kitchen is fair game. You can keep it simple and have students all test the same foods, or give every group something different to test. We recommend choosing at least one acid, such as lemonade, ketchup, mustard, pickle juice, yogurt, or sour cream, and one non-acid, such as mayonnaise, milk, or soy sauce. You’ll need about 1 cup of each for a class of 32.)

For each group of four students (or each solo student), you’ll also need:

  • newspaper or plastic to cover work areas
  • baking soda (about 1 tablespoon; 8 groups need about half of a 1-pound box)
  • baking powder (about 1 tablespoon; 8 groups need about 7 ounces)
  • vinegar (about 2 tablespoons; 8 groups need about 2 cups)
  • water (about 2 tablespoons; 8 groups need about 2 cups)
  • 2 craft sticks or spoons (for spooning out powders; 8 groups need 16 craft sticks or spoons)
  • 7 small paper cups: 5 for testing known substances, and 2 for testing unknowns (We used 3-ounce bathroom cups, also known as Dixie cups. For 8 groups, you’ll need a total of 56 cups.)

For each pair of students working together (or each solo student) you’ll need:

  • a sheet of Press’n Seal sealable plastic wrap; you can also substitute taped-down waxed paper (For 8 groups, you’ll need 16 sheets.)
  • a few toothpicks (for mixing samples)
  • paper towels (for cleanup)

Step 3: Print out materials

Each table will need:

Each pair of students will need:

Each student will need:

Here is a "Results Answer Key" for you to reference if needed.

Step 4: Prepare for class

Cut straws in half to make short straws. Students will use these to transfer drops of liquid. (Full-length straws are likely to tip over cups.) For a class of 32, we suggest you cut 20 full-sized straws in half. That gives you 5 short straws per group—3 for initial testing and 2 for testing unknowns.

Make the purple indicator liquid. For a class of 32, you’ll need about 1 cup. (If you’re using black beans, put 1 cup of beans into 2 cups of water and leave them for at least an hour. The beans will soak up some water and turn the rest purplish brown. If you’re using purple cabbage, put 2 cups of chopped cabbage in 1½ cups of water. Leave it for at least an hour, stirring occasionally. The cabbage will turn the water purple.)

To distribute each group’s materials quickly and easily, we recommend you set up three supply stations.

Station A: Acid Reaction Supplies

  • “Acid Reaction Supplies” sheets (1 per group)
  • a cup containing 2 tablespoons of water (1 per group)
  • a cup containing 2 tablespoons of vinegar (1 per group, labeled “V” with marker so students can quickly tell it from the water)
  • short straws (2 per group)

Station B: Testing Supplies

  • “Testing Supplies” sheet (1 per group)
  • a cup containing 2 tablespoons of baking soda (1 per group; note that you may want to tell students that baking soda is different from baking powder)
  • a cup containing 1 tablespoon of baking powder (1 per group, labeled “BP” with marker so students can quickly tell it from the baking soda)
  • a cup containing 1 tablespoon of purple indicator liquid (1 per group)
  • craft sticks or spoons (2 per group)
  • short straw (1 per group)

Station C: Unknowns

  • a cup containing 1 tablespoon of each unknown substance used for testing (we recommend two test substances per group, each in its own cup)
  • a short straw for each test cup
  • a toothpick for each test cup


Teacher Tips

The purple liquid that you prepare from the cabbage is called an indicator. There’s a pigment in purple cabbage that changes color when it reacts with an acid or base. You and your students should notice that the color of the cabbage juice changes to a reddish/pink when you add it to any of the acids (e.g. vinegar). You can then use this information to test unknown liquids. If the liquid turns pink, then it’s an acid. You can learn more about cabbage juice indicator here.

You and your students will also notice that when baking soda is mixed with vinegar, there is fizzing that indicates an acid-base reaction. Baking powder will also fizz with vinegar. But you will notice that baking powder will also slightly fizz when water is added. This is because baking powder is actually a mixture of baking soda (base) and cream of tartar (acid). This is why it reacts with both water and vinegar.

Mystery 4: Chemical Reactions

The Great Goo Experiment

This Mystery develops the idea that chemical reactions create new materials that have useful and interesting properties. In the activity, students conduct an investigation to determine if the mixing of various substances results in a new substance.

This is a two-part activity. In Part 1, students experiment by combining different substances and watching for reactions. In Part 2, students make “Mystery Science Goo” in ziplock bags and observe its properties. If the activity is running long, you can save the second part for another day.

Step 1: Think ahead

If you have a class or group of students, students can work in pairs and share supplies with others at their table or pod. To figure out quantities of supplies, start by figuring out many pairs and how many tables you’ll have. Individual students can work alone.

Step 2: Gather equipment and supplies

To prepare for the activity, you’ll need:

  • a permanent marker
  • a ruler
  • a measuring cup
  • a teaspoon for measuring (abbreviated as tsp)
  • a tablespoon for measuring (abbreviated as Tbsp)
  • a bottle that holds at least a half gallon (check the recycling bin)
  • a bottle that holds at least a pint (check the recycling bin)
  • a large jar or bowl for mixing glue and water
  • lots of water

The table below shows supplies with amounts needed for a pair of students or a single experimenter, and also for a class of 32 students working in pairs. Since each pair shares supplies with another pair of students at a table, you need one set of testing supplies for each group of four students.

Supplies for Part 1 (Testing for a Reaction)

Supply Quantity for 1 Pair or Individual Quantity for 16 Pairs Working at 8 Tables Notes
Set of printouts (2 pages) Answer Key for Teachers 1 set 16 sets Each pair of students needs a set of printouts.
White vinegar 1 Tbsp ½ cup
Milk 1 Tbsp ½ cup
Borax powder 2 tsp 2 tsp You will mix this with one cup of water. Note that you’ll need more borax powder for Part 2.
Baking soda 1 tsp 1 tsp You will mix this with one cup of water.
Elmer’s multipurpose glue 1 Tbsp 4 Tbsp (about 1/4 cup) White school glue may not work. You will mix glue and water in equal parts. Note that you’ll need more glue for Part 2.
Toothpicks 10 80
Press ’n Seal 1 sheet 16 sheets You can substitute sheet protectors if you have them.
Prepared straws 7 56 Each of these is half a straw, prepared as described in Step 4. Each pair of students needs a straw for the water cup. Groups of 4 will share straws for other cups.
Paper towels 2 32 Note that you may need more paper towels for Part 2.
Newspaper Enough to cover a table Enough to cover 8 tables
Small cups 6 48 These cups are used for supplies that are shared when working with another team. We used 3-ounce plastic bathroom cups. If you use paper cups, be aware that vinegar will leak through some brands after an hour and a half. Plan accordingly. Note that you’ll need more cups for Part 2.

Supplies for Part 2 (Making Goo)

Supply Quantity for 1 Pair or Individual Quantity for 16 Pairs Working at 8 Tables Notes
Borax powder 2 tsp 6 tsp Borax is used in Part 1 and Part 2. The total for 32 students doing both parts is 8 tsp (about 1/6 cup).
Elmer’s multipurpose glue 1 Tbsp 18 ounces White glue is used in Part 1 and Part 2. The total for 32 students doing both parts is 22 ounces.
Small cups 4 (two for each experimenter) 64 (two for each experimenter) Small cups are used in Part 1 and Part 2. The total number for 32 students doing both parts is 112 cups.
Paper plates 2 32
Ziplock baggies 2 32
Paper towels (optional) 2 32

Step 3: Mix your solutions before class

To make the baking-soda solution, mix 1 cup water and 1 tsp baking soda in the one-pint bottle.

To make the glue mixture, mix equal amounts of glue and water in your mixing jar or bowl.

To make the borax solution for Part 1 of the activity (for up to 32 students), mix 2 tsp borax powder with 1 cup of warm water. It is okay if all of the borax powder doesn't dissolve.

To make the borax solution for Part 2 of the activity (for a class of 32), mix 6 tsp of borax with 3 cups of water in a half-gallon bottle. If you have just a few students, you can use your leftover borax solution from Part 1.

Step 4: Prepare and set up your supplies before class

To prepare the straws, follow these steps:

  • Cut each straw in half (Note: Long straws may cause small cups to tip over).
  • Lay the straws side by side with their ends squared up.
  • Eyeball ½ inch and draw a line with your permanent marker across the straws, as shown below.

straw setup

To prepare the testing supply cups, follow these steps

  • Count out 6 cups for each group doing the activity.
  • Use a permanent marker to mark cups for each group.
    • W for Water
    • S for Baking Soda solution
    • B for Borax solution
    • G for Glue/water mixture
    • V for Vinegar
    • M for Milk
  • Put 1 Tbsp of the supply in each cup.

To make Mystery Goo in Part 2, each student will also need:

  • 2 Tbsp of glue/water mixture in a small cup
  • 1 Tbsp of borax solution in a small cup


Borax, while safe when diluted, can be a mild skin irritant to some people, especially those with sensitive skin. If you are concerned, you may want to consider having your students wear gloves or use one of the alternative recipes here .

Mystery 5: Gases & Particulate Nature of Matter

Bag of Bubbles

In this Mystery, students investigate and model how gases cause explosions. In the activity, students experiment by combining baking soda and vinegar inside a sealed bag and observe how the gas bubbles produced cause the bag to inflate–and sometimes pop! This Mystery includes two activities: a baking soda and vinegar explosion in a plastic bag (carefully designed to avoid a mess), and a hands-on particle model that helps students understand why the plastic bag explodes.

Number of students:
Clean-up Supplies (Ex. Paper Towels)
1 roll
Scissors
30 pairs
Baking Soda
4 cups
Dixie Cups (3 oz)
30 cups
Measuring Cup
1 cup
Plastic Plates (10")
15 plates. You can also use large, sturdy paper plates.
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Plastic Spoons
30 spoons
Solo Cups (9 oz)
16 cups. You can use any plastic container that can hold about 1/2 cup of liquid.
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White Vinegar
4 cups
Ziploc Bags (Snack Size)
30 bags. We do not suggest using sandwich size bags because they need more vinegar and baking soda to inflate, and the resulting explosion is likely to overflow the plastic plate.
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Safety Glasses
30 pairs
Capturing Chaos printout Print 30 copies
Stretchy Bag Templates printout Print 8 copies

Prep Instructions

We strongly recommend that students wear eye protection for this activity.

We suggest students work in pairs for the first activity, and in groups of four for the second activity. Students working alone will need a partner for the first activity, and a few friends to help with the second activity.

Prepare the Vinegar and Baking Soda

Separate your plastic cups (or plastic containers) into two separate piles. For each of the cups in one of the piles, pour about ½ cup of vinegar. For the other cups, pour about ½ cup of baking soda into each.

Separate Supplies for Easy Distribution

For the first activity, students will need the following supplies, plus a recommended pair of safety goggles for each person:

Bag of Bubbles Supplies

In the second activity, students will work in groups of four and will need the following materials:

Bag of Bubbles Model Supplies

You may want to separate these for ease of classroom distribution.