Need help on Experiment for Plant Hormone Ethylene

NJNETSFAN · Post by **NJNETSFAN** » Thu Jan 18, 2007 7:59 pm

OK, so I did all my research on this project: https://www.sciencebuddies.org/mentorin ... ?from=Home
and I went to go get the supplies so I can do the experiment for it for my Science fair and I'm having a problem getting the chemicals I need. It says you can order them online, but the website they tell you seems like its not a secure website and it is very confusing to navigate. Since the chemicals I need are so hard to find, I was going just go out and buy liquid iodine with potassium iodide in it, does anyone know if that would work to get show the starch in the plants? IF anyone knows of another way of testing for starch or a place to get the chemicals I need with links that would be great! I really need to get this experiment going as my science fair is due on February 6th. This is my first science fair and I want to make sure I do everything right. Thanks again.

NJNETSFAN · Post by **NJNETSFAN** » Fri Jan 19, 2007 7:31 pm

Anyone know of an alternate way to find starch in plants?

MelissaB · Post by **MelissaB** » Sat Jan 20, 2007 8:20 am

Hi,

If you can find the solution you described, I believe the experiment would work. I'd suggest testing it on some fruit to make sure before you actually do the experiment, but it sounds like it's the same thing as the experiment asks you to make.

NJNETSFAN · Post by **NJNETSFAN** » Sat Jan 20, 2007 8:27 am

I have been able to find iodine with 35% potassium Iodide in it, but its colorless. I tried it last night, and you can see some change, but its not as noticeable as the page says it would be. So I guess I would need to get iodine with potassium Iodide in it that isn't colorless. I've tried a small medicine shop in the town I live in, Eckerd, and I just went to Walmart with no luck. Any idea on where I can get this stuff online. I figure as long as I can get this experiment going by next wednesday-thursday I should be good and will be able to make the deadline.

MelissaB · Post by **MelissaB** » Sat Jan 20, 2007 8:42 am

I think you're going to have to get it from a biological supply company. Note that those websites won't be secure until you actually go to pay for something. Hmmm. After looking around, it looks like the supply company Science Buddies sent you to won't sell these items to individuals, only schools. Can you have your teacher order these items for you?

NJNETSFAN · Post by **NJNETSFAN** » Sat Jan 20, 2007 9:11 am

I will ask about it on monday. The supply sites seem to have limited desription on the Items they sell so it looks like you really need to know what your ordering. I asked my teacher about getting potassium iodide the other day, and they do have it, but she can't give it to me outside of school so I would have to do the experiment inside school. But I still would need to get iodine. Do you know if the solution would have to be clear or the normal color of iodine? I assume that clear would work, and that starch would change the color of the solution, but I'm unsure.

MelissaB · Post by **MelissaB** » Sat Jan 20, 2007 9:18 am

I'm not a chemist so I can't say for sure--but I think you want the purple kind so you can stain your fruit purple. Also, you want iodine crystals, not iodine liquid.

If your teacher has a hard time figuring out what to buy, post back here. However, here is the website for buying the iodine crystals: https://www2.carolina.com/webapp/wcs/st ... =&crumbs=n. You would need the second item on the list, the 30g crystals for $11.65.

NJNETSFAN · Post by **NJNETSFAN** » Sat Jan 20, 2007 9:23 am

Thank you so much! THe only thing I'm not sure about is whether or not my teacher has the potassium iodide in a liquid or crystal form. Now I just have to hope the school doesn't block out this site so I can show her the link. Thank you so much!

MelissaB · Post by **MelissaB** » Sat Jan 20, 2007 9:48 am

You're welcome! You might want to write it down just in case, even though I know it's a very long URL.

NJNETSFAN · Post by **NJNETSFAN** » Sat Jan 20, 2007 9:49 am

I will do that, Looks like I'm going to be paying a lot for shipping though, just to make sure I get it in time. Thanks again

NJNETSFAN · Post by **NJNETSFAN** » Mon Jan 22, 2007 4:34 pm

I was able to get a premade solution of Iodine/ Potassium Iodide in school today from one of the Chemistry teachers, so I'm going to do the experiment in schoool. Thanks again for all the help. Also if you look at the project link, they just updated it today and said that you can't get the chemicals by yourself(great to know when ur 3/4 of the way threw it)

MelissaB · Post by **MelissaB** » Mon Jan 22, 2007 5:33 pm

I'm glad you were able to find a solution of the chemicals. Did you test them to be sure that the stain worked?

The reason the site was updated was that when I realized you couldn't order the chemicals yourself, I notifed Science Buddies Administration and asked them to change the write-up for the experiment. I didn't want other students to have the same problem you were having. I'm sorry that we didn't notice it until you had an issue with it!

NJNETSFAN · Post by **NJNETSFAN** » Mon Jan 22, 2007 5:41 pm

I'm pretty sure the solution will work. The teacher asked me what the solution was for and and I told her that is was to test for starch in plants and she knew exactly what I was talking about so it should work. I have midterms all week so I won't be able to do the experiment in school until Thursday after school. I'll have to keep this site in mind for next year as it seems like its a really good site and to see that there's people like you here that's another plus.

NJNETSFAN · Post by **NJNETSFAN** » Thu Jan 25, 2007 9:29 am

I just got home from school, and the experiment worked.

MelissaB · Post by **MelissaB** » Thu Jan 25, 2007 2:42 pm

Wonderful

. Congratulations!