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20

The dropping mercury electrode (DME) is a working electrode made of mercury and used in polarography. Experiments run with mercury electrodes are referred to as forms of polarography even if the experiments are identical or very similar to a corresponding voltammetry experiment which uses solid working electrodes. Like other working electrodes these ...


12

Most likely, mercury was used as a colorant, specifically red. This list shows mercury providing a red color in flame tests, and the same would presumably be seen in fireworks. Several other, less dangerous elements also give red or reddish colors. This site identifies lithium as providing the color in red fireworks, and also mentions lithium carbonate ...


10

In "Fireworks, the Art, Science, and Technique", Takeo Shimizu gives a very good explanation of color production. For blue, the color-producing firework chemical is thought to be copper monochloride. If there is no free chlorine in the flame, there can be no blue color.The discovery of colors produced by chlorine along with other elements belongs ...


10

Could it have caused irritation or injury? Possibly, but not likely, depending on a few factors: The intensity of the emitted ultraviolet. Proximity to the light source. Length of exposure. You'd need to calculate the dosage integrated over time. That said, it is very unlikely any harm was done, because of the following: The power supplies are limited to ...


9

Related only - but posted as an answer as, while not 100% what you asked about, it's related enough to be worth noting. In the past some angle detection or motion detection switches used rolling mercury as a bridge between two metal contacts. The term "Mercury switch" was commonly used. The Mercury is necessarily inert relative to the associated ...


9

As iron is one of few metals not forming amalgams, Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. ..it should preferably contaminate the mercury surface. I would try, perhaps repeated, dropping mercury, e.g via punched filtration paper to sulphuric acid bath. It can be combined ...


9

Don't use a mixture, just use pure Hg. Chill to 4.2 K, conveniently reached with liquid He, and all magnetic fields are excluded. Levitate on a magnet, sans yogi. Mercury in a static magnetic field, with direct current, forms a simple homopolar electric motor, creating a vortex. A safer way (sans neurotoxic Hg) to demonstrate a homopolar motor requires just ...


9

TL;DR - You need two different lamps, one that has a phosphor to absorb the 254 nm light, and one that doesn't. Alternatively, you can use one lamp, and use a filter to select the wavelengths. Mercury vapour lamps emit a significant amount of both UV-C light (around 254 nm) and UV-A light (around 365 nm). This includes fluorescent bulbs used for lighting a ...


6

The Diphenylcarbazide Test for the presence of mercury was used as early as 1920s. However, since the test is very delicate (the test can detect $\pu{250 \mu g/L}$ mercury in solution), it has been used predominantly in neutral solutions, until it have been adapted to Quantitative Analysis Scheme by Scott in 1929 (Ref.1) to ditect in acidic medium: The ...


5

The process you described would be more appropriately called "reduction of mercury(II) to elemental mercury". Unfortunately, the trick with iron likely won't work (something more inert like copper would be a better choice though). Mercury(II) oxide is weakly basic, so mercury salts in general would easily undergo hydrolysis and form basic oxosalts in ...


5

Chelation therapy, which is a very effective way to treat heavy-metal poisoning, is a chemical process in which a synthetic solution is injected into the bloodstream to remove heavy metals and/or minerals from the body. British Anti-Lewisite (BAL) was one of the first chelating agents to be developed as an anti-dote for war gas, dichlorovinyl arsine (Lewsite)...


5

Lead, mercury and other heavy metals form complexes with both monodentate and polydentate ligands. But the complexes made with polydentate ligands like EDTA are much more stable than with monodentates. Usually metallic complexes become toxic if the central metallic ion (non-complexed) is released or not entirely surrounded by ligands. Monodentate complexes ...


5

I found this statement in a paper about $\ce{Hg}$ contamination from dental work: The evaporation rate of elemental mercury at room temperature ($\pu{20 ^\circ C}$) is approximately $\pu{50 \mu g\:cm-2h-1}$ (range of $\pu{40-60 \mu g\:cm-2h-1}$). They cited the following work as a source for that number: Gary N. Bigham, Wanyu R. Chan, Manuel ...


5

In the beginning of the $20th$ century, the following procedure was developed to prove the presence of mercury in solution. One drop of the solution to be tested is deposited on a filter paper which had been dipped into a freshly prepared 1% alcoholic solution of diphenylcarbazide. Mercury salts produce a purple spot, even in a very diluted solution. ...


5

Why $\ce{HgS}$ and not $\ce{HgO}$? Because of HSAB. F'x has already answered a previous question of why mercury has propensity towards thiols(or in general sulfur). Quoting the relevant information: In Pearson's HSAB theory (hard and soft acids and bases), the reason the $\ce{S-Hg}$ bond is be stronger than the $\ce{O-Hg}$ can be explained because $\ce{S^2-...


4

I am afraid that no one knows why! The superficial rationalizations such as HSAB and ionic size etc are good for decorating general chemistry textbooks. As scientists, we should accept the fact that all questions which a human mind can generate do not have answers. Unfortunately, as science students, we are trained that every question must have an answer at ...


3

Keep in mind that "stabilizing" orbitals does not "prevent" electrons from being shared, only that they would be shared to a smaller extent. The very fact that mercury is a liquid and not a gas shows that there is some bonding in mercury, even if it is weaker than the bonding in most metals. So, it is conductive the same way other metals are, just less ...


3

To spare everyone watching the movie (and giving revenue to someone showing fake chemistry), here is a summary: A container labeled "27/27 | 99%999 | 1/Kg | 001200300 | RED MERCURY | W. GERMANY | WARNING - DANGEROUS | WARNING - OPEN IN LAP" containing a red liquid is first inverted, then a metal wire (safety pin) is placed on it. The metal wire ignites. ...


2

There are several redox reactions can be taken place when you add household beach on elemental mercury metal. However, this question is more like a homework question. Thus, I give you insight to the answer and you may read a bit and find out what's happening. This reaction is studies and results have been published (Reference 1), the abstract of which states ...


2

Synthesis routes From molbase[dot]com : Phenylhydrazine + urea -> 1,5-Diphenylcarbazide ~96% yield Pasha; Madhusudana Reddy Synthetic Communications, 2009 , vol. 39, # 16 p. 2928 - 2934 Phenylhydrazine + urethane -> 1,5-Diphenylcarbazide + 1-Phenylsemicarbazide + Ammonia Journal of the Chemical Society, vol. 53, p. ...


2

An old method of electrolytic production of sodium from water solution uses a mercury cathode. It is "inert" in regard to not taking part in the electrolysis itself. It dissolves sodium and prevents it from reacting back with water.


2

Said by other words, you do not believe that $3 + 2 = 3 + 2$ There are 2 $\ce{Hg}$ columns, sharing the same pressure at the bottom. Both have the same height, so the pressure difference is the same. Yet you have doubts the pressures at their tops are the same. Pressure at A = Pressure at B +pgh It should be $p_\mathrm{A} = p_\mathrm{B} + \rho gh$ where $\...


1

Your terminology makes seeing the correct picture harder. Part of the problem is that the pressure at A is could be at any point in the column of mercury and that is not constant. The pressure in the column of mercury varies with height (depending on the weight of mercury above that point). When you fill the tube with mercury and invert it there is no ...


1

Light and Ozone Production Ozone is generated not by UVC or UVA but by Vacuum UV (VUV) in the 100-200nm wavelength range 1. Low pressure mercury lamps generate strong VUV (184nm) and UVC (254nm) light, and medium pressure lamps generate light at various frequencies in the range of 200nm-600nm 2. When it's said that UVC light is disinfecting or ...


1

Non-amalgamation of mercury with iron means that the iron is not dissolved, and therefore floats on the surface as a dross. However, non-amalgamation does not mean total insolubility. If a few ppm of iron needs to be removed, washing with a dilute solution of HNO3 might be best, with much agitation. There will be some dissolution of mercury to Hg++. That's ...


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