Growing piezoelectric crystals experiment

[JessicaHelena]

Homework Statement

I'm not sure if this is a forum for these kinds of things. But anyways, at school I and a handful of other kids are devising an experiment to send up to ISS to test it over a period of 30 days next year. (Yep, we're quite fortunate to have this opportunity!) We've chosen to grow piezoelectric crystals using (super)saturated solution of the piezoelectric crystal salts and using a seed crystal attached to a string so that hopefully the crystals will grow along the string. However, so far we've had little success (or frankly, no success) and the deadline's coming soon, so we are quite worried. It seems that sometimes we oversaturate the solution that at some point they turn mushy and solidify, or other times the seed crystals just dissolve before any other crystals have had a chance to form.

Homework Equations

I don't think there's any relevant equations needed at this stage of the experiment.

The Attempt at a Solution

Here's the procedure we followed (for using supersaturated solutions):
- We have 20 ml distilled water in a beaker at room temperature.
- Using a measuring spoon, we put in little amounts of piezoelectric crystals and dissolve it thoroughly until the distilled water + crystals solution becomes clear again.
- We repeat the step above, until we have stirred long enough but we still see bits of crystals undissolved.

In earlier experiments, after this step, we've tried heating up the beaker since heating up makes the solution absorb more salts. When we cool it down in a pan full of ice, that's when the solution turns all mushy and solidify, and we had to heat the beaker up again (lightly) to get it back to liquid state. I think some of those experiments succeeded in creating crystals (and others failed) but none of them would grow crystals along a string we put inside.

In later experiments, since we didn't think heating up the solution was so good of an idea, we just dissolved the salt in room temperature. That too, worked irregularly.

Most importantly, since we are given 30 days in a microgravity environment, we don't want to be done in just a couple of days and have nothing else to do. However, all our experiments so far, if successful, produced crystals in about a day, which worries us. How can we lengthen the duration of the experiment?

 

[Borek]

Have you tried to estimate by how much the solution is supersaturated and how large crystal can be grown before the solution is just saturated and any crystallization stops?

You can always try to add some excess substance into the solution so that they keep the solution saturated. For thermodynamic and kinetic reasons small crystals will dissolve and will be replaced by growing large ones.

 

[Borek]

Cross post, locked here.

https://www.physicsforums.com/threa...g-piezoelectric-crystals.960814/#post-6093634