imp

All my classical chem. texts say, in essence, pure water has a Ph of 7.0. Also, pure water may be obtained by distillation. My book on building a live steam locomotive, under boiler care, claims distilled water has a Ph of about 5.5! (??). That's what started my wheels turning. I bought steam distilled water from 3 different sources; all checked out acidic, one as low as 5.0. That's low enough to corrode my boiler tubes! Obviously, the Ph is easily adjusted upward, probably with baking soda. However, can someone come up with an explanation whether the texts are wrong, or something funny is going on with the distilled water? (Textbooks CAN be wrong. My calculus text claims pistons in an automotive engine move in Simple Harmonic Motion. They don't). Thanks for your input! Imp.

One of my suppliers does not offer Formaldehyde, or Formalin, but only Paraformaldehyde. As I understand it, perhaps not quite correctly, paraformaldehyde is an isomer in powdered form. My question specifically is, if gentle heating liberates formaldehyde gas, can someone tell me whether volume/pressures obtained are adequate to bubble the gas through water to obtain formaldehyde solution? Can 37% be achieved. Or, is some other scheme possible to utilize paraformaldehyde. My mother-in-law is coming to visit soon! Imp.

Ah, yes, ionized liquid content of foodstuffs, I forgot! And after the fact of the post, my wife assured me she did on a few occasions, witness arcing unexpectedly. For general interest, the Shar Micro-Convection oven have a metallic turntable, instead of glass/quartz, and apparently the loading effect on the magnetron is calculated to avoid arcing. My store-wrapped Arby's sandwiches once caught fire; the wrappings contained aluminized paper. Imp.

I believe the argument implied FILLING the tank full of water. Yes, liquids are slightly compressible, most less than 1% at 3,000 psi. Forgive use of antiquated units, it's the way I learned things in the Frozen Water Age. Thought we were talking about storage tanks for gas products, not rockets. But thinking things through is what we're all here for, right? Imp.

Hey, maybe I'm more dense than water, but it's incompressible. So, if you fill a tank with it under pressure, suddenly release that pressure (like break off the valve), a little bitty squirt of liquid will be evident, and the pressure will then be zero,. and nothing further will happen. This is why pressure vessels like boilers are proof-tested for containment strength and leakage by using liquid, generally water, as the medium, instead of gas. Am I all wet here? Imp.

In all the time my wife has sold microwave ovens, and taught cooking classes, I don't believe I've ever heard of meat products behaving as described. Perhaps the sausages had free-metallic ions in them? I would get a new microwave AND different sausages! Imp.

Some gases, such as oxygen, helium, and nitrous oxide, for example, are stored, transported, and used from high-strength cylinders having very high internal pressure, perhaps several thousand pounds per square inch (psi). The witches' tale about such cylinders is that if one is tipped over and the valve broken off, the "jet propulsion" action of the released gas will drive the tank forward at dangerous speed. Can anyone confirm/deny the truth in this old tale? Imp.

Mishaps with nitric acid are very easy to occur. Be careful about breathing the acid fumes; if you can smell it, you have already inhaled too much. Imp.

KNO3 can be used for ALL SORTS of effects in pyrotechnics. The potassium content causes violet flame color, while the oxygen content provides for combustion. Also, potassium nitrate is used to preserve meats, under the name "salt peter". In some of the wars in the last century it was fed to soldiers for reasons not to be considered here. It is not a violent oxygen-providing compound, so other less stable nitrates and chlorates are often used. Most oxidizers can be quite dangerous, so stick to the academics until you are sure of what you can expect. Imp. (BTW, black powder as mfd. commercially, is not a simple mixture containing KNO3. The process is a bit more involved than just mixing)

Why don't you build a Tesla coil? You could learn a lot about electricity, and those things are sure to amaze your friends (and Faculty). It's not all that difficult. If you would like, I can coach you, if you get in touch with me. (I taught Math one year, but didn't like it). Imp.

Cookies, the number being raised to a power is called the "base". To multiply two or more bases raised to some power, we add the exponents, keeping the base the same. Two non-identical bases raised to some power CANNOT have their exponents added. FYI, similarly, two like bases raised to some power may be DIVIDED by subtracting their exponents. Imp.

Hello! I'm a guy who always needs to know how/why things work. If there are any members who are also members of the "gun culture", as I am, there are quite a few questions which have troubled me for years. One is the gas dynamics of small arms propellant (powder). Does anyone have knowledge of about when the gas pressure peaks when, say, a typical rifle is fired? Is it after the projectile (bullet) leaves the shell casing within the arm's chamber? Certainly, it must be before the bullet travels any appreciable part of the barrel's length. Another question: Smokeless powder "burns" at a rate dependant on the pressure surrounding it. But, the constituents, typically guncotton or nitroglycerin, or a mixture of both, can be "detonated", that is exploded, by an appropriate shock. How then do the dynamics of smokeless burning in a gun barrel avoid detonating? Detonation, as I understand it, is an uncontrolled dissociation of a compound into more simple compounds, or elements. Thanks in advance for any input! Imp.

Hello! Have you yet been successful at finding some magnesium metal? You did not state what quantity you sought. Regarding engine blocks, I am in doubt of the claim stated; 97% magnesium is quite weak, and not suitable for highly stressed mechanical parts. Powdered magnesium often reacts easily with water; therefore, it must be handled and stored properly, and cannot be readily shipped by public means without entering the "hazardous materials" domain. Again, how much do you need, and where are you located? Imp.