Physical Change or Chemical Change?

After cold delays (yep, welcome to the South), ice delays, cancelled field trips, and a snow day, we FINALLY had regular school days Thursday and Friday. The good news is, we're looking at 71* for Wednesday's high! Maybe winter is finally over. 

A couple of weeks ago, my students completed a lab experimenting with physical and chemical changes. In their words, "This was the best science class EVER!"

We started by reviewing evidence of physical changes and of chemical changes and watched a StudyJams video. As they watched, students added facts to their bubble maps that they may have missed previously. 
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Then, we prepared our notebook for our experiment: 


Students prepared their data tables to include a space for their hypothesis:

Now let the fun begin!

Our first change included combining tea mix and water, pretty basic and definitely a physical change. 

Change number two was baking soda and vinegar - much more exciting! One of my groups poured the vinegar in too slowly, so it wasn't as exciting for them. Be sure to tell students to just dump the whole cup of vinegar into their baking soda cup. 
Also, be careful because originally, I labeled our baking soda cups as BS. Whoops!

Our third reaction was definitely the most fun and it was the first time I had tried it. We made "elephant toothpaste." Students mixed water, yeast and hydrogen peroxide for an exciting exothermic reaction. Make sure that students stir vigorously or it will not work as well. They loved that it overflowed AND that heat was created - their excitement was so revitalizing. 
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After groups completed their experiments, they had to write a conclusion paragraph and justify their results. "I know that baking soda and vinegar was a chemical reaction because..." Once we started discussing between the groups, I was able to find the misconceptions that students held. A big one was that when we stirred our tea mix and bubbles were made, it was a chemical change. 

Good news, your students will be better prepared for their experiment because I have created an experiment packet for your groups! Head on over to TPT to find it for FREE!





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