Found on the web somewhere. Its mine now.

Yeah, you have to click on it to get the full-size image (unless you have microscopic vision).

Tony Writes:

Hi, Im 14 years old and Chemistry really is my favorite subject in school,
and out. I had a question about CO2. Is it possible to break the bonds that
hold the CO2 molecules together?
ex.passes through something and carbon is trapped and air passes on?
Thanks a lot

Yes, it is possible to break the bonds that link the carbons to the oxygens in CO2. However, doing so is not easy, and outside the laboratory there is only one practical way to do this. CO2 is very stable and non-reactive, which is why it survives so long in our atmosphere, and contributes to global warming.

Scientists are working on a method for transforming carbon dioxide (CO2) into fuel, using catalysts and sunlight. However, it could be decades before this can be done on a large scale So there still really is only one way to convert large amounts of carbon dioxide (CO2) into oxygen (O2) – Photosynthesis.

Yep. What scientist have been able to do only with great difficulty – and usually with dangerous substances and expensive equipment – nature has been doing for a billion years with ease.

I know that “plant a tree” wasn’t the answer you were looking for, but photosynthesis is still the most efficient way to purify CO2, and it probably will remain so for another century or so.

Ghazal asks:

Dear AaC,

Hi, I am an engineering student, and I will be working on remediation of TCE using ZVI. My problem is that TCE is very volatile, so it’s hard to know how much of exactly I have, for example, if i wante a 50mg/l concentration, by the time is added, weight, how can i know how much i have in my vile ? I will also be using a GC, but the problem with that also is that i have to define concetrations for it, before i can give it an unknown concentration. ANother problem is that i need to make my viles are anaerobic as possible, but the ones that i have tend to contain a bubble of air in them as soon as put the cap on it. how can i avoid that?
thanks alot

Translation: Ghazal is (I believe) using a permeable reactive barrier (PRB) made of zero-valence Iron (ZVI) to reduce toxic Trichloroethylene (TCE) to non-toxic ethylene and water. In general, the system works by passing contaminated groundwater through the ZVI-PRB which de-chlorinates the TCE, so that only purified water passes through to the other side. He states that he will be using a gas chromatagraph (GC) to examine his samples before and after the remediation process in order to determine how effective the process is.

Solution
There are two ways to reduce the evaporation rate.

1. Lower the temperature. TCE freezes at -90 C. It is fairly easy to find a commercial freezer that can go down to -50 C or lower. If you place all of your equipment, including your sample of TCE in the freezer for about an hour, and then (quickly) take it to the lab and measure your sample, you should lose very little of your TCE due to evaporation. If you are in Canada, you can just go outside and do this.
2. Reduce the surface area. If you weigh your TCE into an extremely narrow glass tube, and then quickly cap it once you have your measured amount, you can assure minimal loss of TCE due to evaporation.

The only way to eliminate the problem of oxygen in your samples is to use a nitrogen blanket to displace the oxygen. Prepare your samples under a nitrogen blanket and then cap them so they are not contaminated with oxygen.

Benjamin Writes:

Dear AaC,

I am doing an assignment on removing certain inks and ethyl acetate seems to
do it best. I need to know whether i am able to dilute ethyl acetate in
water so as to reduce the quantity of purchase.

Ethyl Acetate is in a class of compounds known as Esters. Like most esters, Ethyl Acetate has a slight fruity smell. It is a non- to slightly polar molecule. Although it mixes well with other solvents, such as acetone, ethanol, and benzene, it is not terribly soluble in water.

According to the literature, ethyl acetate has only an 8.3% (by w/v) solubility in water, so you would not see a great savings if you were to mix some water into it. However, you may be able to mix in a less expensive solvent that is miscible with ethyl acetate and make a small savings that way.

. . . Roger Kornberg of Stanford University in California! Come on down, Roger!

(the Crowd goes wild)

Doctor Kornberg won the Nobel Prize in Chemistry for his work on the underlying chemistry of the DNA transcription process, which has helped to deepen our understanding of the gene-replicating process.

Roger Kornberg, Circa 1970
**Note that the shirt is now back in style

Source: Chemist wins Nobel prize for gene-reading breakthrough

No chemistry site is complete without a mention of laboratory safety.

Obviously a real scientist and not just a model, is injured in a dangerous conflagration ignited by some chemicals or something

There. Now if you don’t know everything there is to know about lab safetly, I don’t know what else I can tell you.