Baking Soda and Vinegar

Yesterday we had a lot of fun with vinegar and baking soda trying out lots of different little experiments. The first idea I got from Teacher Tom and it was the first experiment that we did. I put about 1/2 a cup of vinegar in the bottom of the bags and then put about 2 tbl. of baking soda in half a paper towel and then folded that up and put it in the bag (quickly zip locking, squeezing out what air I could) and then we sat back and watched as they slowly bloated with carbon dioxide. In theory the bags were supposed to pop open like a little bomb, however, we used quart sized freezer Ziplock bags and instead of popping they stretched just to the brink of explosion and then the air/liquid leaked out.

The second experiment merely consisted of a small vase half filled with vinegar and then added a little over a tablespoon of baking soda and watched as it foamed up and over the edges. The best part of this experiment was asking the kids prior to dropping in the baking soda what they thought would happen. "I think the glass will shatter" and "I think the glass will blow up" were some of the best.

The third experiment was more exploration based and was stolen from Child Central Station. I filled two cake pans with baking soda (just covering the bottom with a significant coating of the powder) then I half filled little cups with vinegar and food colouring that matched the colour of the cup. I then took straws and cut them in half (1 for each child), I wish I had turkey basters like in the fore-mentioned blog post. Having 14 kids it was a little hectic at first, but after a few minutes over half of them decided they were done and moved on to play time while I stayed with the remaining handful as they continued to explore. With fewer children we started pouring the cups of vinegar into the pans and watched the coloured bubbles expand and then disappear; it was quite enjoyable.