The methyl violets are aniline dyes which consist basically of three aniline molecules conjugated at the center and with varying degrees of methylation of the amine groups. Structures:

http://en.wikipedia.org/wiki/Methyl_violet

I want to know what is the “theoretically ideal” solvent for these molecules (we don’t necessarily know which of the three configurations it is).
From experimentation I already know that they are soluble in water, in glacial acetic acid, and in ethoxyethanol > ethanol > methanol. However those are just “textbook” examples of common solvents and that information is already widely know. What I am really asking is, given the choice of any solvent or combination of solvents which are liquid(s) at room temperature, what would you choose from the point of view of solubility theory? Would aniline itself be a good choice? Are there some generalizations which can be made about the solubility of the methyl violets looking at the structures and the functional groups ?

Sorry for the delayed response. I’m assuming you want to know the activation barrier for 14C + O2 => CO2. I haven’t seen any theoretical or experimental data on this, though I did search. There are activation barrier differences for hydrogen vs. deuterium, but there’s probably not a significant energy difference for 14C vs. 12C, since we’re talking about a 16% mass difference (while H vs. D is ~200%).

But if you want an exact difference in activation barrier, it’s not hard to calculate it theoretically. Send me an e-mail if you’d like me to compute an exact number.

Perchlorate is a chemical species (a complex anion) used for a variety of chemical reactions, analyses, some fertilizers, but mostly in rocket fuels and explosives. (Perchlorate solids can decompose explosively.) There is some concern about concentrations of perchlorates in food and water — largely because it can interfere with the uptake of iodine into the thyroid. The exact level of concern has been difficult to establish, which is why there are few exposure limits.

In February 2005, the U.S. Environmental Protection Agency (EPA) established its official reference dose of perchlorate at 0.0007 milligrams per kilogram per day, and translated that number to a Drinking Water Equivalent Level (DWEL) of 24.5 parts per billion (ppb). This level is consistent with the recommended reference dose included in the National Academy of Sciences’ (”NAS” or “NAS Committee”) January 2005 report on the health implications of perchlorate.

(I suspect none of that is particularly news to David, but I felt I should answer his question. He had some other remark, but I suspect it was meant as a rhetorical question and so I will not address it.)

Geoff Hutchison ‘99 is answering chemisty questions for the local paper in Ithaca. He offers to answer ours as well. Do you have any questions for Geoff? Here are mine: 1) Is percholate really that dangerous? 2) Are you as…