LanthanumK's Blog

I have compiled a list of sources for the elements that are available to the amateur chemist. Dysprosium will be discussed here.

Dysprosium is one of the less reactive rare earth metals. Its compounds are trivalent and generally colorless, although the soluble compounds supposedly have a yellow solution. Dysprosium is quite a boring rare earth metal.

In element form: Dysprosium alloys are used on many hard disk platters. Terfenol-D, the alloy in a Soundbug(r), contains dysprosium metal.

In compound form: No sources found.

Here is my sample of dysprosium. It is a hard disk platter.

I tried to extract pure chromium metal from a stainless steel spoon. It turned out to be much more difficult than I expected.

I had two extraction theories. One was to oxidize the electrolyzed chromium to chromate(VI), reduce it to chromium(III) in aqueous solution, precipitate it as chromium hydroxide, dry it, and react it with magnesium powder in a thermite-type reaction to make chromium metal.

Another was to use the chromium(III) in aqueous solution and electrolyze it to produce chromium metal at the cathode.

Trying it was a different matter.

First, I anodized the spoon in salt water solution. A huge amount of metal hydroxides were produced. I filtered them and placed the paste in sodium hypochlorite to oxidize the chromium(III) to chromate(VI). However, I did not realize that the inside of the huge lump of hydroxides still had a large amount of unoxidized iron(II) hydroxide. The oxidation from iron(II) to iron(III) used up most of the oxidative power of the bleach, severely diluting the solution.

Then, I reduced the light yellow chromate solution with ascorbic acid. It formed, as before, a light purple solution of some chromium complex. However, the resulting solution was by now so dilute that nothing could really be done with it.

I took a small portion, added hydrochloric acid and reacted it with zinc metal. No chromium(II) ions were produced in a measurable quantity.

I then took another portion, larger this time, and added some ammonia. Apparently, chromium(III) hydroxide forms a complex with ammonia, preventing it from precipitating anything.

I then reacted the previous ammonia mixture with sodium carbonate. Nothing precipitated.

I then took some more chromium(III) solution and reacted it with sodium carbonate. Nothing precipitate. Apparently, chromium(III) forms a complex with ascorbate.

I then electrolyzed some chromium(III) solution. Nothing happened.

I reduced the remaining chromate to chromium(III) to avoid environmental catastrophe and dumped down the drain.

This page will detail all of the ammine complexes that can be formed with various metals.

Copper(II): Copper(II) ammine complex  shows more information about this complex. This complex may be dried after being washed with an organic solvent, forming an extremely dark crystalline mass that tends to turn whitish in air. I have never done this without hydrolysis to insoluble copper hydroxide.

 Chromium(III): Chromium forms an ammine complex as well. It forms when chromium(III) chloride is reacted with excess ammonia.

Cobalt(III): Cobalt(II) forms several ammine complexes which easily oxidize in air to cobalt(III). I have yet to make some of these.

Nickel(II): Nickel(II) forms an ammine complex when nickel(II) chloride is reacted with excess ammonia. It is much bluer than other nickel solutions.

Silver(I): Silver forms a colorless ammine complex when silver chloride, oxide, carbonate, or nitrate is dissolved in ammonia. Upon standing, it can precipitate dangerously explosive silver nitride. It was used in the past to make silver mirrors by reacting with KOH and glucose.

Zinc: Zinc forms a colorless ammine complex when zinc hydroxide reacts with excess ammonia.

There are several super-strong acids that exist, with highly interesting properties.

Sulfuric acid: The most common of the strong acids, it is the acid that all other strong acids are compared to. Sulfuric acid does not have an extreme ability to protonate substances, but it is a highly reactive substance.

Magic acid: Containing antimony pentafluoride and fluorosulfonic acid, it was called this because of its ability to dissolve hydrocarbons such as paraffin wax. Dissolving a candle in this acid was a magic trick.

Fluoroantimonic acid: This acid contains antimony pentafluoride with hydrofluoric acid. This forms the extremely stable cation SbF6(-), leaving the hydronium ion quite bare.

Triflic acid: one of the earliest discovered superacids, this acid is relatively tame and in common use, but is still much stronger than sulfuric acid.

This is nasty stuff.