Overblog Follow this blog
Administration Create my blog
March 27 2012 3 27 /03 /March /2012 15:37

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

 

Molybdenum is a rather dull gray metal; it is one of the least reflective of the transition metals. It is also quite inert, high-melting, and corrosion resistant. However, it is vulnerable, to heat, like many other left side transition metals; it oxidizes to hexavalent molybdenum trioxide, which is an acidic metal oxide. Molybdenum sulfide, the most common molybdenum ore, is a slippery black substance similar to graphite. Molybdenum forms a wide range of colorful complexes in lower oxidation states such as the molybdenum blues. Molybdenum is insoluble in acids and bases. Its expansion rate is similar to that of silica glass.

 

In element form: Some high speed tool steels have about 0.25% molybdenum metal in them. The support wires for the filament in incandescent light bulbs are often pure molybdenum. The squares of foil used to seal the ends of halogen lamps are pure molybdenum.

 

In compound form: Moly grease contains molybdenum disulfide. Molybdates are used as animal feed supplements.

 

Here is my sample of molybdenum metal. It is the foil seal from a halogen lamp. It is encased in the quartz glass, with wires coming out each end.

 

Molybdenum.JPG

Repost 0
Published by LanthanumK - in Elements
write a comment
March 27 2012 3 27 /03 /March /2012 02:17
I made some iodine by reacting tincture of iodine with some hydrochloric acid and adding some sodium hypochlorite. A solution of iodine monochloride was made because of excess hydrochloric acid. I then added sodium bicarbonate until flecks of iodine precipitated. The iodine then coagulated, making it easy to filter. It was filtered and began drying, although the evaporation was significant. The paper was stained brown all around the iodine crystals, showing that the iodine vapor reacted with the moist starch. I scraped off a bit of iodine when it was almost dry and placed it in a container.
 
Iodine-crystals-on-paper.JPG
 
The iodine in the container was then placed in a hot tap water bath. The coloration of iodine vapor was faintly visible. When the vial is placed in boiling water, however, the coloration is much more intense. When the vial cools, microscopic crystals of pure iodine are deposited on the walls of the vial.
 
Iodine-crystals-at-25-C-deposited-from-vapor-at-100-C.JPG
 
Here is a video of the sublimation:
 
Repost 0
Published by LanthanumK - in Elements
write a comment
March 26 2012 2 26 /03 /March /2012 15:41

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

 

Niobium is a silvery gray, high melting metal from Group 5. It is quite reactive but is protected by a layer of niobium pentoxide. Because of this, niobium is extremely corrosion resistant. Niobium ores are commonly found along with tantalum ores, and the two elements were repeatedly confused in their early days. Niobium forms pentavalent compounds that exist in non-aqeous solution, including the yellow and low-melting pentachloride. Niobium has a relatively low density for a refractory metal.

 

In element form: Niobium jewelry, because it is hypoallergenic, is quite popular. The wires leading into the arc tube for high pressure sodium lamps are made of niobium metal or 99% niobium alloy. Some steels have small amounts (0.1%) of niobium in them. Niobium capacitors, while rare, replace tantalum capacitors in some applications.

 

In compound form: Lithium niobate is used in some piezocrystals. Niobium pentoxide is used in some ceramic capacitors.

 

Here is my sample of niobium metal. It is a mispunched niobium disk sent gratis from Reactive Metals Studio upon request.

 

Niobium-disc.JPG

Repost 0
Published by LanthanumK - in Elements
write a comment
March 24 2012 7 24 /03 /March /2012 17:19

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

 

Zirconium, a silvery gray left side transition metal, is similar to titanium. It is quite unreactive in bulk form but burns vigorously in powdered form, forming zirconium dioxide, which is better known as cubic zirconia when in a crystalline form. Zirconium forms tetravalent covalently-bonded compounds that have low melting points, just like titanium. Zirconium is transparent to neutrons and heat-resistant, making it useful for fuel rod claddings in nuclear reactors. Zirconium is quite corrosion resistant but will dissolve slowly in hydrochloric acid, just like titanium.

 

In element form: Some body jewelry is made of zirconium metal. Some vacuum tubes use zirconium alloy getters. Old flash bulbs for cameras sometimes used zirconium wool.

 

In compound form: Lead titanate zirconate is used as a piezoelectric element. Both zircon (zirconium silicate) and cubic zirconia (zirconium dioxide) are used in jewelry. Zirconium dioxide is also used as an abrasive.

 

Here is my sample of zirconium. It is a lead titanate zirconate (supposedly) piezoelectric element from an igniter.

 

Zirconium.JPG

Repost 0
Published by LanthanumK - in Elements
write a comment
March 23 2012 6 23 /03 /March /2012 12:41

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.

 

Bismuth-and-chloride.JPG

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.

 

Bismuth-chloride-hydrolysis.JPG

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.

 

Bismuth-iodo-complex.JPG

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.

 

Bismuth-chloride-zinc-reaction--4-.JPG

Repost 0
Published by LanthanumK - in Experiments
write a comment
March 23 2012 6 23 /03 /March /2012 12:32

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

 

Yttrium is a reactive gray metal with properties very similar to the rare eath metals. It reacts slowly with hot water and dissolves quickly in acids to form a colorless solution containing trivalent yttrium. It is also found in the same ores with all of the other rare earth metals. Yttrium, though, does not have an f orbital like the rare earth metals and so has some differences. Yttrium, like most rare earth metals, is slightly toxic. Inhaling large amounts of yttrium oxide dust, just like any other form of dust, can cause lung problems.

 

In element form: Some spark plugs contain about 5% yttrium. They are normally marketed as yttrium spark plugs.

 

In compound form: Yttrium oxide is doped with europium oxide to create red phosphors in CRT screens and CFL bulbs. Yttrium vanadate doped with europium is used in mercury vapor lamp phosphors.

 

Here is my sample of yttrium. It is the ground wire from a yttrium spark plug. Since the remainder is nickel, I could not leach the yttrium out by hydrochloric acid.

 

Yttrium-spark-plug.png

Repost 0
Published by LanthanumK - in Elements
write a comment
March 22 2012 5 22 /03 /March /2012 13:19

Copper forms both divalent (cupric) and monovalent (cuprous) compounds. Since most of the cuprous compounds are insoluble, they are relatively easy to prepare.

 

Copper(I) oxide: See here for the red form: Production To make the yellow form, react sodium hydroxide with copper(I) chloride. It will turn bright yellow. Another potential way to make the yellow form is to electrolyze concentrated salt water with a pure copper object as the anode. The anode initially turns white as copper(I) chloride is produced, then turns yellow as the NaOH from the cathode reacts with it. This may not make pure copper(I) oxide, which is susceptible to oxidation by any oxygen produced at the anode as well as air.

 

Copper(I) chloride: React copper(II) chloride (Production) with either ascorbic acid or sodium metabisulfite to form a white precipitate of copper(I) chloride.

 

 

Copper(I) bromide: React copper(II) sulfate with an equal amount of sodium bromide. Add ascorbic acid or sodium metabisulfite. White copper(I) bromide will precipitate.

 

Copper(I) iodide: React copper(II) sulfate and sodium iodide. A dark brown mixture of iodine and copper(I) iodide will form. Add ascorbic acid to reduce the iodine to water-soluble iodide and only a white precipitate should remain. You can also react copper sulfate and a mixture of tincture of iodine and excess ascorbic acid. A white precipitate of copper(I) iodide will form.

 

I reacted copper(II) chloride with a mixture of tincture of iodine and ascorbic acid. Several reactions occurred at once: reduction of copper(II) chloride to copper(I) chloride by ascorbic acid, reaction of copper(I) chloride with copper(II) chloride to form the dark brown complex seen here, reaction of copper(II) chloride with sodium iodide to produce brown iodine and colorless copper(II) iodide, and reaction of iodine with ascorbic acid to form colorless iodide. The end result, after all products were mixed together, was a light brown precipitate.

 

 

Repost 0
Published by LanthanumK - in Experiments
write a comment
March 22 2012 5 22 /03 /March /2012 13:12

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

 

Strontium is a relatively soft, gray alkaline earth metal. It is highly reactive and must be stored under oil to prevent reaction with air. Strontium can replace calcium in bones, making radioactive strontium particularly dangerous to the bones. However, stable strontium is harmless. Strontium is very similar to calcium, with a slightly soluble oxide and colorless divalent compounds. Strontium compounds have a bright red flame when heated, making them useful for pyrotechnics.

 

In element form: No sources found.

 

In compound form: Strontium oxide is used in old CRT screens to absorb the radiation (lead cannot be used in the front of the tube because it darkens). Ceramic magnets are made of sintered strontium ferrite, as well as most ferrite cores. A few toothpastes contain strontium chloride. Flares and red fireworks often contain strontium.

 

Here is my sample of strontium. It is a ferrite core used to absorb electromagnetic inconsistencies.

 

Strontium.JPG

Repost 0
Published by LanthanumK - in Elements
write a comment
March 21 2012 4 21 /03 /March /2012 13:08

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.

 

Beryllium-copper-II--chloride-reaction.JPG

 

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.

 

Beryllium-hydroxide-flashbulb.JPG

 

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.

Repost 0
Published by LanthanumK - in Experiments
write a comment
March 21 2012 4 21 /03 /March /2012 12:36

Rubidium does not have any household sources. Purchasing it can be extremely expensive, and it is similar to caesium, which has some household sources, making purchase sort of repetitious. Of course, if you are buying it for an element collection, you can buy it here: Metallium $110 for 1 g of 99%, $50 for 0.2 g of 99% GalliumSource $140 for 1 g of 99.5% RGB $45 for 0.1 g 99.5%, $70 for 1 g 99.5% (plus Hazmat shipping) or ebay.

Repost 0
Published by LanthanumK - in Elements
write a comment