LanthanumK's Blog

Silver is best dissolved by nitric acid, forming a colorless solution of silver nitrate. However, nitric acid is difficult to obtain, so acetic acid is used instead to dissolve it.

I dissolved some anodized (silver is made vulnerable, not protected, by anodizing) silver in acetic acid and hydrogen peroxide. It formed a milky solution of silver acetate (because of chloride impurities present in the vial). I then placed a piece of copper wire in the solution. Some silver formed as a black coating, but no silver crystals formed because of the insistent decomposition of hydrogen peroxide that was occurring from the copper wire. A purplish precipitate of what I assumed was micro-particulate silver accumulated on the bottom of the vial. When disturbed, it went into suspension. This same precipitate formed when ascorbic acid was reacted with the silver acetate solution.

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I also precipitated some silver carbonate. It formed as a fluffy white precipitate. Once filtered and dried, it turned brown as silver oxide or even elemental silver (from light exposure) was formed.

Silver acetate decomposes on exposure to light. After a day in daylight, the silver acetate was colored slightly bluish because of silver metal that had begun forming from the decomposition.

Because of working with this silver solution, I discovered that just about every piece of equipment I have for chemical experiments is contaminated with chloride ions.

I was looking for a solvent for bismuth metal, which I purchased from a gift shop for the Franklin Mineral Museum. I knew that acetic acid would only form the insoluble subacetate, so it cannot be used. I do not have nitric acid or sulfuric acid, so hydrochloric acid remains. Addition of hydrogen peroxide to the hydrochloric acid allowed the bismuth to be oxidized and the oxide to be dissolved, leaving a solution of bismuth(III) chloride. This solution is dense and colorless, visible as swirls when the dissolving solution is disturbed. The remaining bismuth is pitted and generally corroded.

A large amount of ascorbic acid crystals are added and some tincture of iodine is added as well. The tincture of iodine is decolorized, but no bismuth iodide is produced. I cannot seem to obtain bismuth iodide.

I then added water to the solution, to the top of the vial. The bismuth instantly hydrolyzed in the diluted solution, producing a white precipitate of BiOCl.

When this precipitate is further neutralized with sodium bicarbonate, it turns light yellow as bismuth hydroxide is produced.

After disposal of the relatively nontoxic bismuth precipitate down the sink (bismuth solutions are too acidic to stay as ions in aquifers, so they precipitate and remove themselves naturally), I repeated the experiment. I took some of this bismuth solution and reacted it with an iodide. A yellow iodo complex is obtained.

When this is diluted with water, it turns white again as the iodide hydrolyzes.

I then took some more of the bismuth solution and placed it on a piece of zinc. The zinc turned black as the bismuth chloride was reduced to elemental bismuth. The resulting layer was quite thick.

I wanted to produce beryllium hydroxide as my example of a beryllium compound. To produce this solid, I placed beryllium in copper(II) chloride crystals, then added a few drops of water. An extremely vigorous reaction began, with steam being profusely evolved and the beryllium jumping around. When more water was added, the reaction slowed, but large amounts of copper and hydrogen were still being produced.

I accidentally placed the lid on the container and it popped off 6 feet into the air after a few seconds. When the reaction was over, I let the copper particles settle, then decanted the cloudy (beryllium hydroxide was dissolved in its chloride solution) solution from the copper. Addition of ammonia seemed to solidify the solution. Beryllium hydroxide precipitated as an extremely firm and gelatinous precipitate, colored slightly blue by copper impurities locked inside the hydroxide structure.

Tilting the container up side down made the excess ammonia and liquid run out while leaving the structure of the hydroxide untouched. I added some water and vigorously shook it to dislodge some of the beryllium hydroxide. After stirring with a twist tie and using various other ways to break the hydroxide into small pieces, I finally got it onto filter paper, where it dried to a powder, just as I expected. (Do not breathe fumes, can cause berylliosis!) This powder can be used to generate other boring beryllium compounds.

Have fun with lead chemistry, but be safe with small amounts! All of my lead experiments (I also formed the sulfate, bromide, chloride, dioxide, monoxide, etc.) used about 200 mg of lead, which is quite a small amount of metal.