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Part of our kindergarten science curriculum requires us to teach the difference between a solid, liquid, and gas. This is a really simple and engaging experiment I found for helping students recognize a solid, liquid, and gas.
Ingredients:
plastic water bottle
water
balloon
Alka-Seltzer tablets
Fill the water bottle a little more than half way with water.
Explain to students that the tablet and the water bottle are both solids and the water is a liquid.
Break an Alka-Seltzer tablet in half and drop it in the water.
Observe the reaction between the tablet and the water. Point out the bubbles that are popping at the surface of the water and explain that the reaction created carbon dioxide bubbles (a gas).
Have students draw their observations.
Next, tell students you are going to repeat the activity using more Alka-Seltzer tablets and covering the top of the bottle with a balloon. Have students write and share their predictions of what they think will happen to the balloon.
Add 1-2 Alka-Seltzer tablets to the water and quickly cover the top of the bottle with the balloon. The trapped gas from the carbon dioxide bubbles will cause the balloon to inflate! Here is a time-lapse video:
We decided to find out what would happen if we added even more Alka-Seltzer to the water.
The additional Alka-Seltzer created more gas which got trapped in the balloon and made it inflate even more.
Have students draw what actually happened and write what they learned.
Click here to download the free printable page.
Additional Experiment:
Alka-Seltzer Snow Experiment – Here is another fun and engaging experiment that uses Alka-Seltzer and snow to teach students about the chemical reaction between an acid and a base.
That was an awesome experiment .Thank you
You’re welcome, Lalitha! I’m glad you enjoyed it!
Hello, I am working with 2nd grade students. We have been working with the scientific method and states of matter. I would love to make this experiment with them, but when I get to the data part, I am not sure what can I do to have some kind of graphic done.
Could you give an idea as to what can I measure? and show as data?
Thank you so much in advance.
Hi Marian! The only measurable data I can think of would be the changes in the water level and the size of the balloon. You could mark the water level before adding the Alka-Seltzer tablet and then mark it when it bubbles up and measure the difference. You could also try to measure how big the balloon gets. Hope this helps! Thank you for visiting my blog!
Tina