An Aerobic Exercise: Yeast Metabolism with and without Aerat

[science kid]

hi, i am new to this. i am doing a science projet about "Yeast Metabolism with and without Aeration". i seem to have a problem wit how to collect the carbon dioxide. if you know of any way that i acn collect CO2 please let me know. i don't have a CO2 collecting tool, which is wat my teacher said i would need. it seems to me that i can't find anything beside the $1500 tool that can collect the CO2. so if you know of any household
tool(s) i can use, please let me know.

Thank You!

[carolinethorn]

Hi,

What are you growing your yeast in?

Do you need to demonstrate that the gas is CO2? or just get a measure of how much gas is produced under different conditions?

I have heard of people using balloons to trap gas emitted from flasks of growing organisms.

This website has some details
http://www.chemheritage.org/Educational ... /yeast.htm

best of luck,
Caroline

[geoffbruton]

Hi science kid,

This is an interesting challenge! Do you know if you just have to collect the carbon dioxide or prove that it is there? I don't know how much chemistry you may have studied in school yet, but one of the classic ways of testing for carbon dioxide is to use something called lime water.

I would think that if you were able to make the gas generated by your reaction bubble through some lime water, you would easily be able to prove the creation of carbon dioxide.

I did a quick Google search and came up with some great websites. Check out:

http://chemlearn.chem.indiana.edu/demos/Limewate.htm

http://spikesworld.spike-jamie.com/scie ... oxide.html

http://chainreaction.asu.edu/ecology/tr ... tester.htm

Although these are basic chemical reactions, I think you should be able to think of a way in which to get the gas produced into the lime water... Have a think and let us know your thoughts.

Good luck!
Geoff.

[ChrisG]

As far as a tool to collect gas, one simple approach is to use an inverted test tube (or graduated cyllinder or bottle). Submerge the tube in the solution and let all the air escape from the tube. Then, keeping the mouth of the tube below the solution surface, invert the tube so that it is vertical and the open end is down. Fasten or support the tube in this position. As the microorganisms excrete gas, the undissolved portion will form bubbles and collect at the top of the inverted test tube.

This is basically the same as the procedure that is presented in the project description (step 2 under experimental procedure).
https://www.sciencebuddies.org/mentorin ... ?from=Home