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Rock Candy crystal

Postby srividyaram » Sat Feb 25, 2017 9:16 pm

We used and followed the steps lined up in this website for growing rock candy crystal for my second grader's science project. We have had wonderful growth of crystal around the string as well as in the the glass jar. We noticed that the seeded string didnt necessarily lead to extra crystal growth. Is this in line with what has to be expected? Is there any advantages of seeding for the crystallization?
Thanks in advance for the feedback. Our science project is next Saturday.

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Re: Rock Candy crystal

Postby kaylimasuda » Sun Jun 04, 2017 11:08 am

Hello there,
I apologize for the lack of a response. Seeding is typically done to jumpstart the crystallization process by providing a starting point. Therefore, it is usually expected to have a higher crystal yield. However, crystallization from the string itself can happen, as in your case.

Kayli Masuda

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Re: Rock Candy crystal

Postby cumulonimbus » Sat Oct 07, 2017 9:28 am


Sorry this response is rather late, but to add on to Kayli's answer, the seed crystals on the string can make the solution "supersaturated" and cause more crystals to form; when a supersaturated solution (one that has more solute than it could hold normally) is disturbed, i.e. by putting a string into it, crystallization occurs. However, since both the seeded and unseeded solutions were saturated, the string could have "jumpstarted" the crystallization in both cases, so you might not have noticed much of a difference.

Elena Lee

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