First of all we needed to define What is Chemistry? I didn’t want to go into a long discussion that I knew would be totally over the top of Selena’s head, so instead I had her reflect on many of the experiments we have done in our home and the observations she has been making lately. She quickly identified that heat changes things, cold changes things, and she even remembered that an acid such as Vinegar can create some fun fizzing when added to baking powder.
Her definition of Chemistry was, “The observations of everything in our world and how they change or react with other things.” She went on to add, “How we question the world around us, and make hypothesis which we then test.”
To move on to some fun supporting experiments to support her definition, I allowed her to choose 5 different items from our kitchen, then she had to find one more item besides vinegar that was an acid base.
She chose from top of plate to bottom: Baking Soda, Flour, Sugar, Cinnamon, and Salt. We already knew we would use Vinegar, so her other item she guessed was an acid base was a lemon.
Selena made a hypothesis on what would happen when we added the Vinegar to these items. Of course she already knew that Vinegar and Baking Soda fizzed. She expected the Vinegar and the other ingredients to do the same thing.
She was quite surprised to our results.
Baking Soda and Vinegar fizzed, Flour and Vinegar the vinegar actually moved away from the flour. Sugar and Vinegar the Sugar absorbed the Vinegar (but at a rate that appeared as though you could watch the vinegar moving across the sugar.) The Cinnamon and Vinegar was very surprising and exciting, as the Vinegar actually jumped away from the Cinnamon. The Salt and Vinegar again like the sugar absorbed the Vinegar, but quickly and not as easily to see the movement of the vinegar through the salt.
The results with the Lemon were very much the same as with the Vinegar, but with more intensity. It was fun to really watch the lemon juice jump away from the cinnamon.
As I am typing this Selena is listing other observations she wants to make on the white board, she has listed how heat changes water, she is drawing her guess using small circles to represent droplets and atoms. Stay tuned as we have more fun exploring the world of Chemistry.