Friday, October 23, 2015

first science experiment

I am not so great at creative crafty things and unfortunately science experiments fall into that category. Or maybe I'm just somewhat lazy. Both are true probably. We only do science experiments when I feel particularly motivated or they're really easy. Last week (6 weeks into the school year) the stars must have aligned because both of those things happened and we finally got one done.

I bought this new 2015 Usborne Science Encyclopedia for Noah for the next few years - it's above Evie though. But I'm sure she gets something out of the readings...I hope. We like it very much, after adjusting to the increased difficulty of the content, and especially that we can use my new iphone to scan the QR codes in each lesson for additional follow-up information. 

This lesson was about how molecules (water in particular) want to stay together due to their mutual attraction to each other. Because water molecules are more attracted to each other than air molecules,  they form this surface tension between the water and the air sort of like a skin. It's this surface tension that allows water bugs to skate across water, or in our case, allows needles to float.

We were supposed to use tissue paper but since I didn't have any, toilet paper stood in just fine. Though it's hard to tell, the toilet paper absorbed the water and fell to the bottom of the bowl, leaving the needle to float on top of the surface. The kids thought it was cool.

Maybe easier to see? We watched a video on my phone where a dude floated a bunch of aluminum coins together and they formed a natural group, being attracted to each other. But then he (and we) added a drop of dishwashing liquid into the water and it was enough to disrupt the water molecules attraction (and their surface tension) and the needle sunk. 

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