Continuing my blogging project for 2011 where I do a science experiment per week with my seven year old daughter.
Since we consumed a gas in last week’s experiment, I thought this week we could do the opposite and create a gas using those old standbys: vinegar and baking soda. Since we were at Grandpa’s house this week, it made for a nice easy experiment and I got to raid his kitchen cabinets for supplies:
- Baking Soda (sodium bicorbonate)
- A balloon
- A bottle or vase with a narrow mouth
(Sorry for the quality of the photos. I forgot to bring a CF card for my camera, so I had to use Ger’s point-and-shoot and backlit lighting to boot.)
I explained to Sam the concept of a reaction –that some things change when they mix with or even just touch other things. That change create a lot of interesting things, including creating a gas. I told her that baking soda and vinegar would make a gas when they mix, and asked her what she thought would happen if I mixed them together and put a balloon over the mouth of the bottle. Sam wrote in her journal:
Experument 6: Makeing gas. I prdikt that the dlon will explode.
Yes! Explosions! With that in mind, I poured a few cups of vinegar into the bottle, filled the balloon with baking soda, and stretched the tip of the balloon over the mouth of the bottle without letting any spill in. I then told Sam to upend the balloon and dump the powder in:
The reaction –in all sense of the word– was pretty great. The mixture fizzed violently and the balloon started to expand like a big fat exclamation mark, which actually caused Sam to shriek and dive under the table, fearing that her prediction was seconds from coming woefully true:
Honestly, I got kind of alarmed myself for a second; the book hadn’t provided any guidance on the amount of mixture to create, and I had just begun worrying about the best way to get globs of baking soda and vinegar off of a ceiling when it finally eased off. Instead, I ribbed Sam about her squeamish reaction and made her practice her maniacal mad scientist laugh and give me ten good shouts of “I’LL SHOW THEM! I’LL SHOW THEM ALL!” to make up for it.
Then she finished writing in her journal:
The ballon bloow up. The vineger and the baking soda made a gas.
Next week: we waste more foodstuffs while learning about density.