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UVC is very harmful to people and requires specialist equipment to create and use safely You are not going to be able to create or use lamps that emit 222nM light without specialist equipment, and even if you could it would almost certainly not be safe. Far UV lamps are widely commercially available for germicidal applications and these usually use mercury ...


3

Question: What is the practical significance of the shape of conical flask (in US: Erlenmeyer flask)? An Erlenmeyer flask (also known as a conical flask or a titration flask) is a type of laboratory flask, which consists of a flat bottom, a conical body, and a cylindrical neck. The flask is created by the German chemist, Richard August Carl Emil Erlenmeyer (...


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No, it is not a good disinfectant. To quote from the CDC on chemical disinfectants 'Guideline for Disinfection and Sterilization in Healthcare Facilities (2008)' available here: Methyl alcohol (methanol) has the weakest bactericidal action of the alcohols and thus seldom is used in healthcare 488.


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I'll do the "full problem". First the volume of a liquid typical increases with a rise in temperature. Since no temperature was specified, one must be assumed. The 88th CRC Handbook of Chemistry and Physics gives 1.0361 g/cu cm at 20 °C. So to work the problem you must assume: (1) The density of 99.8% propylene glycol is 1.0361 g/ml @ 20 °C Note: For a ...


2

Here is related material I once posted: Also, commentary in Bretherick, Volume 1, page 23-24, to quote: A student mixed aluminium foil and drain cleaner in a soft drink bottle, which started emitting gas. Another student carried the bottle outside and was claimed to have been overcome by the toxic fumes [1]. Most drain cleaners are alkalis, so that ...


1

Personally, I don't mind the odor from aluminum foil, whatever little there may be. Aluminum foil (household style) contains aluminum and its hard-to-separate sesquioxide (Al2O3), but also oil from the manufacturing process used to make it. If the odor you are sensing really comes from the foil, then that might be it. (though in my opinion unlikely) If so, ...


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Your first result is OK. But : First, it does not make any sense to give a result with $\ce{10}$ significant figures when the initial data has only $\ce{2}$ significant figures. When a data is given like here $\ce{1.8 x 10^{-5}}$, it means that the author cannot be more precise, and may admit that the exact value of $\ce{K_b}$ is somewhere between $\ce{1....


1

Ascorbic acid in solid crystallic form is much less sensitive to light and oxidation, compared to its solutions ( especially if in ascobate form ). Another lucky consequence is only the outer layer has been exposed to the light, the inner bag content is not disturbed. It is hard to quantify the impact. Empirical evaluation could be if it changed the colour ...


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