About a year ago I made some homemade valentines cards for my youngest son to give out to his class at preschool. We made valentine’s cards that included a small baking soda heart glued on, and made them a few days in advance, just to make sure they had time dry. The day of his valentine’s day class party, we carefully placed his cards in a box, and headed off to school. But when we got there, I realized several of the baking soda hearts had broken apart. Thankfully, my son didn’t notice, and he cheerfully delivered his cards to his teacher. I, on the other hand, was deteremined to find a way to re-engineer the handmade valentines cards to prevent the hearts from breaking again.
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After spending some time thinking about our broken hearts, I realized what we needed was a binder. In chemistry, a binder is a substance that makes things stick together. The simplest example of a binder is glue, so I added some white glue to my heart mixture, and voila! I had a much stronger heart!
- 1/2 Tablespoon white glue
- 4 Tablespoons hot water
- 9 Tablespoon baking soda
- red food coloring
- small bowl
- small heart cookie cutter
- wax paper
- red construction paper
- card stock
Step 1: Pour 4T of hot water into small bowl.
Step 2: Add 1/2 Tablespoon of glue to the hot water, and stir until the glue is mixed well.
Step 3: Add 10 drops of red food coloring to the glue/water mixture.
Step 4: Add 9T of baking soda into the red glue/water mixture, a little bit at a time. Mix well.
Step 5: Place the heart cookie cutter on a piece of wax paper, and pour a little bit of the mixture from step 4 into the heart. Leave the cookie cutter in place for 5 minutes.
Step 6: Remove the cookie cutter, place it on a new place on the wax paper, and repeat step 5 until you have the number of valentines you would like to make. Leave the hearts to dry overnight.
Step 7: Fold the red construction paper in half, then in fourths. Unfold the paper.
Step 8: Cut along the creases of the paper to make eight rectangles.
Step 9: Print the valentines below onto white cardstock paper. Cut out all eight valentines.
Step 10: Glue each valentine from step 9 onto one side of a piece of cut construction paper from step 8.
Step 11: Print the instructions for the hearts, below:
Step 12: Cutout the printed instructions from step 11, and glue them onto the back of each valentine.
Step 13: Glue the dried hearts on the front of the card.
We made 33 valentines for my boys’ classes, and each one was so excited to give them to their friends!
Back at home, we decided to try out some of our leftover hearts, and boy were we in for a surprise! The binder in our hearts (the glue) seem to prevent the bubbles from our baking soda and vinegar reaction from popping! In other words, the addition of a binder to our mixture increased the surface tension of the bubbles in the reaction! Our unexpected result gave us bigger and longer lasting bubble explosions!
First we filled a cup with 1/2 cup of vinegar then dropped a heart in to see what would happen.
We wanted a bigger reaction, so we experimented with starting more vinegar. For our second reaction, we started with 3/4 cup of vinegar.
Wow! The reaction was so much bigger with a little more vinegar. We even learned we could help the reaction by swirling the cup. I love that our homemade valentines cards don’t include any candy, and show kids the fun of chemistry!