Science Buddies: "Ask an Expert"

I am doing the effects of exercise on carbon dioxide project from science buddies and my solution that is suppose to turn yellow is not turning yellow when i breath into the tube? Could anyone trouble shoot this for me?

Moderator note: Science Buddies guidelines request that you only post your question once. I have removed the duplicate post. Thank you.

Hi cadenjace1,

I'm assuming that you're working on the project described here:

https://www.sciencebuddies.org/science- ... ?from=Blog

Did your solution start out green or blue-green in color as shown in the project procedure (under Building Your Respirometer)? If not, you might try making the solution again using distilled water as suggested in the procedure.

Did you see bubbles in the solution while you were breathing into the tube? If not you might try repositioning the tube in the bottle so that the end of the tube is submerged in the solution.

How long did you breathe into the tube? If your breathing time was sort, you may need a bit more breathing time for the reaction to take place.

I hope this helps. Please ask again if you have more questions.

A. Norman