Theory Thursday: Mini Volcanoes

I saw this idea on Pinterest, though the link led to only a picture and not a blog. It is such a simple activity and takes seconds to set up, yet the result never get old. The kids always find the reaction of vinegar and baking soda fascinating. Vinegar (acetic acid) and baking soda (sodium bicarbonate) react to form carbonic acid. Since the carbonic acid is unstable, it immediately breaks down to carbon dioxide and water. The bubbles are the result of the carbon dioxide escaping.

The kids don't care why it works. They're just happy that it does.

You'll need vinegar, baking soda, food coloring (optional), something to contain the baking soda, something to hold the vinegar, and something to dispense the vinegar.

Mix the vinegar and food coloring in the cups and dump baking soda on the plates.

Next comes the fun!

 Squirt the vinegar on the baking soda to make it bubble and foam.

The more vinegar you use, the bigger the reaction will be.

And the bigger the smile!

It'll make little craters all over the plate.

Continue making volcanoes until they no longer form.

Then you'll need to dump it and fill the plate with fresh baking soda so you can do it all over again!

And again. Until you empty your baking soda box and need to purchase more.

Of course, they weren't done though. They dumped it all in a bowl, like the rain in a jar experiment, and continued experimenting.

 And just like before, they made a big mess and we transferred outside.

They added grass, sand, sticks, water, and whatever else they could find. They tested theories and mixed potions. For over an hour. 

The analysis? Lots of hands-on learning fun.

So, whether you're erupting mini volcanoes or continuing further exploration, take time to investigate the laws of science.

And have fun!

Theory Thursday: Shiny Pennies

We've been doing a lot of money counting lately (and it's not because we got our taxes back.) We've practiced with fake coins, M&M's, chocolate coins, and real money. I even had them help me separate and roll coins. (Ok, that was more for me than them, but they don't know that!)  Jake knows how to count pennies and dimes well and is getting pretty good at nickels. This week's experiment coincided well.  

Supplies:                                        
A few old, dingy pennies                Non-metal bowl
1/4 cup white vinegar                     Paper towels  
1 teaspoon salt                               2 cute helpers (optional)             

Directions:
1. Pour the vinegar into the bowl, add the salt, and stir.
2. Put the pennies into the bowl and count to 10 slowly.
3. Take out the pennies and rinse them in water.

Gather your supplies.

Add vinegar and salt.

Stir.

Drop in the pennies.

Slowly count to ten. Then rinse with water.

Admire their shininess!

Chemistry is at work here. Since vinegar is an acid and reacts with salt, it removes the dulling copper oxide, leaving the penny shiny again.

Repeat the process without rinsing with water.

The penny will turn greenish blue as malachite forms.

Leighton explained to Jake and Alyssa that this is the reason the Statue of Liberty is green. Jake thought it was pretty cool and proceeded. to recite the Pledge of Allegiance for us. He was even more impressed though that the "vinegar smelled like ketchup." Oh, and that they got to keep the pennies in the end.