Friday, October 2, 2009

Growing Crystals

After reading a bit about crystals, we decided to grow our own!
I chose this experiment for salt crystals because it was the easiest and fastest- growing one I could find at the time. I admit it - I'm impatient.

I'm hoping that next week we can try our hand at making sugar crystals (a.k.a. rock candy!), but there's a bit more involved with that - hopefully we'll have time for it.

For these salt crystals you'll need:

-Equal parts table salt, vinegar, and hot water (The recipe says you can also add an equal part of laundry bluing - whatever that is - but it's not necessary.)
-Paper plate
-Toilet paper tube cut with fringes at top (see photo below).

Mix together salt, vinegar, and hot water in the plate.

Set toilet paper tube on plate.

Depending on your humidity, you should have some crystals within 24 hours.

Here is how ours looked after two days:

We were excited to find that we did indeed have a lot of crystals before the first 24 hours was over, but there wasn't enough of a build up for my camera to do it justice.

And after 7 days...

Notice how some of the crystals are turning a yellowish color. From what we've learned about crystals, we're thinking it's because all of the liquid has evaporated, and there is no moisture left to "feed" the them. They're sort of drying up now. They were much prettier and more sparkly after about Day 4, which was probably when they were at their peak.

This Squidoo lens has an assortment of different "recipes" for growing all kinds of crystals. If you scroll down the page to the "YouTube Video of Salt Crystals", you can watch that to see a time-lapse version of the experiment we did. We were pleased with how ours turned out, but the one in the video is really neat - especially with the way they time-lapsed it. I showed it to our kids before actually doing the experiment, and they wanted to know if ours would grow that quickly. :)

This was a very worthwhile project - one that the kids really got into and looked forward to observing and touching everyday.

1 comment:

  1. Shannon, It has been a while since I have commented on your blog. I look forward to each entry though. This one happens to touch on what we will be experimenting in our next class. I was going to make the sugar crystals (rock candy), but I also like this idea with the salt. I think doing both is good as children and adults like to see things happen quickly, so while the sugar crystals are growing the salt ones will grow fast. I think I will try the time lapse photos too. Thank you for the idea, also the links to Squidoo. Keep up the great work! Is the music new? It is beautiful. How do you do that? Kathleen


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