Hydrogen is another abundant element that’s great to study with kids. We spent a class learning about where we find hydrogen and its properties. We also explored heat producing chemical reactions with hydrogen.
This post is part of a series on chemistry that’s based on a homeschool co-op course that I taught.
Because hydrogen is the simplest of elements, we can use it to introduce the concept of an atom. Hydrogen only contains one proton and one electron. This video gives a great explanation of how to build larger atoms.
One of the fascinating things to me at least is that hydrogen is found in ordinary, everyday things like water and in awesome stuff like stars and gas planets. This is a good time to point out that the prefix hydro- (and hydra-) means water. We also talked about the commonly-used chemical equation H20. I encourage kids to use H20 when writing about their lab. I know some of them like the idea of getting to take a shortcut on writing.
I liked these videos for learning more about where hydrogen can be found in celestial bodies.
Experimenting with Hydrogen
For our lab activity, we took a look at chemical reactions. First we did the classic baking soda + vinegar and then we watched hydrogen peroxide + yeast. Using a thermometer, we measured the changes in temperature and decided which one was an example of an exothermic (heat producing) reaction. Spoiler alert, it’s the hydrogen peroxide and yeast.
I really like this exercise for explaining the topic of chemical reactions. In both situations we have noticeable changes in the appearance of the substances used. We also get the temperature changes that are easily read on the thermometer and felt when holding the cup. Also, bubbles are always exciting.
It’s important to note that in this example, yeast is acting as a catalyst, making the natural decomposition of hydrogen peroxide go much faster. You can find many versions of this demonstration online. I used this one as a guide.
A great extension of this would be to investigate other examples of exothermic and endothermic reactions.
We also went outside and did a supremely fun and messy demo with even more hydrogen peroxide, yeast, liquid soap and food coloring. I didn’t bother getting any sort of higher concentration of hydrogen peroxide and the results were still great.