LanthanumK's Blog

This will be my last elements post. I may be posting less often in the future due to work.

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

Bismuth is the left-most metal on the periodic table and the only metal with more than four valence electrons. (All other such elements are nonmetals or semimetals.) Bismuth is a silvery gray metal that develops a pinkish hue on exposure to air due to the formation of an iridescent oxide layer. When bismuth is crystallized from a melt in air, the surface becomes multi-colored due to the formation of this oxide layer. Bismuth is one of the least toxic heavy metals, making it useful for replacing the more toxic lead. Bismuth is quite inert, with an activity slightly above copper. Therefore, it is insoluble in normal acids. Its compounds are prone to hydrolysis in aqueous solution. Bismuth is extremely slightly radioactive; the half-life of the dominant bismuth isotope is over a billion billion years. Its radioactivity was unnoticed until 2003.

In element form: Bismuth fishing sinkers and ammunition are relatively common, but expensive. Bismuth crystals are available for sale from mineral shops. Some lead-free solders are made with bismuth alloy.

In compound form: Pepto-Bismol contains bismuth subsalicylate.  Some internal deodorants have bismuth subgallate in them. Bismuth oxychloride is used in some cosmetics to obtain a shiny effects.

I have several sources of bismuth, but no pictures.

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

Lead is a soft blue-gray metal well known for its rather high density, although a significant number of elements exceed the density of lead. Lead is rather inert to many corrosive substances such as hydrochloric and sulfuric acid, but vulnerable to others like acetic acid. Soluble lead compounds are mostly colorless, while the insoluble ones can be either colorless (lead carbonate) or colorful (lead iodide). Lead is one of the few elements that forms insoluble halides. Lead chloride can be dissolved in hot water, while lead bromide is pale white like silver bromide and lead iodide is bright yellow, much brighter than silver iodide. All of them can dissolve to a significant extent in hot water. Lead has a low melting point and is easy to extract and shape, making it the ideal metal for many applications. However, its toxicity is necessitating a replacement of lead by other elements such as bismuth, which are more expensive, less dense, and more brittle. The banning of lead pellets for shooting of birds in wetlands is one such example. Lead forms a sulfide ore that forms large cubic crystals, known as galena. Lead also forms cerussite, which is lead carbonate and was used as a white pigment for many years. Crocoite, lead chromate, is a bright red mineral that was also used as a pigment until it was discontinued.

In element form: Lead fishing sinkers, bullets, and wheel weights are still relatively common. Lead acid batteries contain spongy lead metal on the anode. Tin-lead solder can be dissolved in hydrochloric acid, leaving lead behind.

In compound form: Lead white pigment contains lead carbonate. Lead glass contains lead silicate. Lead acid batteries have lead dioxide cathodes. Piezocrystals can have lead titanate or lead zirconate titanate in them.

Here is my sample of lead. It is a wheel weight containing about 95% lead.

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

Mercury is one of the two liquid elements on the periodic table and the only metal that is liquid. Well known for its toxicity and interesting properties, mercury is a fascinating element to experiment with. Mercury itself is a mobile (easily flows), silvery gray, and dense metal. Under certain conditions, it may form a skin of orange mercury(II) oxide, although my mercury has never done this. Mercury forms alloys with many elements known as amalgams. Mercury is found in the ore cinnabar, which consists of red mercury(II) sulfide. When it is roasted in air, it forms mercury vapor, which can be condensed to form pure metallic mercury. Sometimes cinnabar is oxidized by air, forming droplets of native mercury, which are the only liquid mineral. Mercury is a rather inert metal, but it dissolves in oxidizing acids to produce various colorless mercury salts. Mercury(II) chloride, the most common source of mercury ions, is a colorless, highly toxic, and water-soluble solid. Most insoluble mercury compounds are brightly colored.

In element form: Old tilt switches contain beads of mercury metal. These can be found in old thermometers, barometers, and blood pressure sensors. Mercury vapor bulbs have mercury vapor and sometimes mercury metal in them. Fever thermometers used to contain mercury metal. Dental amalgams contain 50% mercury. Fluorescent bulbs contain tiny amounts (5 milligrams or so) of mercury vapor. High pressure sodium bulbs have sodium amalgam in them.

In compound form: Cinnabar is made of mercury sulfide.

Note: Unfortunately, there are no photographs in this document. I have, can produce, or can obtain the pictures of a large number of compounds, but posting hundreds of pictures in one post is difficult because of size restrictions on the hosting site. Instead, there are links to pictures. While most of these link to a JPEG file, there is no guarantee that all of these links are safe. Most are.

The elements on the periodic table form simple inorganic compounds with a wide range of color. Nowhere is this more evident than with the transition metals, although most elements have their own uniquely colorful compounds.

Below is a list of elements with a few of the colorful substances pertaining to each element. Radioactive elements such as plutonium and uranium are not included. This list makes no claim of completion; many elements have dozens of inorganic and organometallic complexes with vastly different colors and properties which are not mentioned here at all.

Alkali metals: The alkali metal compounds have no visible color from the metal. Other ions may contribute their coloration to a compound.

Alkaline earth metals: The alkaline earth metal compounds have no visible color from the metal. Other ions may contribute their coloration to a compound.

Aluminium, boron, gallium, and indium: None of these elements form any colored compounds when pure. Aluminium chloride is often colored slightly yellow.

Antimony: antimony trisulfide – dark gray or yellow, hexachloroantimony(V) acid – greenish, antimony(III) bromide – colorless solid and yellow liquid, antimony(III) iodide – red, ammonium antimony(IV) bromide – black, antimony(V) oxide – pale yellow, sodium thioantimonate(V) – yellow

Argon: See “Noble gases”.

Arsenic: arsenic – yellow or gray, arsenic(III) iodide – red, arsenic(II) iodide – red, realgar – red, arsenic(V) sulfide – yellow

Barium: See “Alkaline earth metals”.

Beryllium: See “Alkaline earth metals”.

Bismuth: bismuth(II) chloride – black, bismuth(III) bromide – yellow orange, bismuth(III) iodide – black, tetraiodobismuthate(III) - red orange, bismuth(III) oxide iodide – red, bismuth(III) oxide nitrite – light yellow, bismuth(III) oxide – light yellow, sodium bismuthate – light brown, bismuth(V) oxide – red, bismuth(III,V) oxide – brown

Boron: See “Aluminium, boron, gallium, and indium”. Boron - gray crystals or red brown powder.

Bromine: bromine – dark red liquid, cesium dichlorobromide – yellow, sodium hypobromite – yellow, bromine nitrate – pale yellow

Cadmium: cadmium sulfide – yellow, cadmium selenide – red, cadmium(II) oxide – white or brown

Caesium: See “Alkali metals”. Caesium forms many colorful complexes with halogens which are mentioned under each specific halogen.

Calcium: See “Alkaline earth metals”.

Carbon: Metal carbides often have a gray or blackish coloration. potassium carbide – copper colored or bluish gray, tricarbon disulfide – bright red liquid, carbon diselenide – bright yellow liquid

Cerium: Cerium dioxide - light yellowish. Cerium(IV) sulfate – bright yellow orange, cerium(IV) fluoride – brown powder, cerium(IV) ammonium nitrate – red

Chlorine: Chlorine - light yellow green, Sodium hypochlorite - light green in solution, chlorine dioxide -bright yellow green gas, dichlorine monoxide - brown gas, dichlorine hexoxide - red liquid

Chromium: chromium(II) chloride solution - blue, chromium(II) fluoride – dark green, chromium(II) iodide – brown, chromium(III) chloride – purple anhydrous and green hexahydrate with purplish gray or greenish gray or grayish solution, chromyl fluoride – red brown gas, chromyl chloride - red liquid, chromium(IV) fluoride – brown with blue vapor, chromium(III) oxide – blue green solid, alkali metal chromates – bright yellow, dichromates – orange, trichromates – red (left one in picture), chromium(VI) oxide – reddish purple, chromium(III) phosphate – grayish brown, chromium(II) acetate – dark red brown, chromium(III) acetate – purple blue

Cobalt: cobalt(II) chloride - blue anhydrous and pink hexahydrate, cobalt(II) ammine complex – tan, cobalt(II) bromide - green anhydrous and pink hexahydrate, cobalt(II) iodide - black or yellow anhydrous and pink hexahydrate, cobalt(II) oxide - olive green, cobalt(II,III) oxide – black, cobalt(II) hydroxide - red or blue, cobalt(III) sulfate – green, sodium cobaltinitrite – yellow, cobalt(II) carbonate - indigo, cobalt(II) phosphate – purple, cobalt borate – tan, cobalt chloro complex - violet to greenish-blue, cobalt(III) ammine - orange or purple

Copper: copper – pinkish red, copper(I) oxide - yellow or red, copper(II) oxide – black, copper(II) carbonate – green blue, copper chloro complex – green to yellow, caesium copper(II) chloride – red orange, copper(II) chloride – brown when anhydrous and green or blue hydrate, copper(II) bromo complex – brownish or purplish, copper(II) bromide – black, copper(II) hydroxide – blue solid, copper(II) sulfate – gray anhydrous and blue pentahydrate, copper(I) acetylide – brown, copper(II) ammine complex – deep blue, copper(III) periodate complex - dark red

Dysprosium: dysprosium(III) chloride – yellow, dysprosium(III) nitrate – pale yellow

Erbium: erbium(III) oxide – pink, erbium(III) chloride – pink, erbium solutions - yellow

Europium: europium(III) oxide – pale pink, europium(III) carbonate - yellow, europium(III) chloride – yellow, europium(III) sulfate – pale pink

Fluorine: fluorine – brownish gas

Gadolinium: See “Rare earth metals”.

Gallium: See “Aluminium, boron, gallium, and indium”.

Germanium: germanium(II) oxide – yellow or brown, germanium(IV) iodide – orange red, germanium(II) iodide – yellow

Gold: gold – golden yellow, gold(I) chloride – yellow, gold(III) chloride – ruby red solid and yellow solution, potassium gold(III) chloride – light yellow, gold(III) oxide – black or brown, gold(I) sulfide – brown, gold(III) sulfide – black,  gold(I) cyanide – yellow

Hafnium: hafnium(IV) iodide – red

Helium: See “Noble gases”.

Holmium: holmium(III) oxide – pale yellow or pink, holmium(III) chloride – yellow or pink

Indium: See “Aluminium, boron, gallium, and indium”.

Iodine: iodine – blue black crystals and purple vapor, iodine monochloride – brown liquid, iodine trichloride – orange or yellow, triiodide solution – dark brown, potassium dichloroiodide – orange, dibromoiodide – red, tetrachloroiodide – golden yellow, iodine(III) nitrate – yellow, diiodine tetroxide – yellow, cationic iodine - blue green

Iridium: iridium(IV) oxide – blue black, iridium(III) oxide – pale green, iridium(III) chloride – green, potassium iridium(IV) chloride – olive green, iridium(IV) chloride - purple or tan or green, tetrachloroiridate(IV) - deep red

Iron: iron(I) nitrosyl - green brown solution, iron(III) chloride – yellow brown solutions and solid, iron(II) chloride – yellow green solution, green hydrate, iron(III) bromide – black, ferrates in solution - light magenta, iron(II) hydroxide - white to greenish gray, iron(II,III) oxide - black, iron(III) oxide - red orange or brown, basic iron(III) acetate - red, ferric nitrate - light purplish, iron(III) ammonium sulfate – yellowish or purplish, Prussian blue – blue, ferricyanic acid - yellow or brown solution, potassium ferricyanide - red, tetrachloroferrate(III) - yellow, potassium ferrocyanide - light yellow

Krypton: See “Noble gases”.

Lanthanum: See “Rare earth metals”.

Lead: lead(II) oxide – light yellow or red, lead(II,IV) oxide – bright red, lead(IV) oxide – dark brown, lead(IV) chloride – yellow, ammonium lead(IV) chloride – yellow, potassium lead(II) iodide – light yellow, sodium metaplumbate or orthoplumbate – yellow, lead(II) sulfide – gray , lead(IV) sulfate – white or yellow green, lead(II) iodide – bright yellow to red, lead(II) chromate – bright yellow

Lithium: See “Alkali metals”.

Lutetium: See “Rare earth metals”.

Magnesium: See “Alkaline earth metals”.

Manganese: permanganate solutions - magenta, solid permanganates - dark purple, manganate(VI) solutions - green, manganate(V) – blue, manganese(III) chloro complex - brownish, manganese(II) chloride - light pink, manganese dioxide - black, manganese(II) hydroxide – light tan, manganese heptoxide - greenish or reddish oil, manganese(III) sulfate - dark green, caesium manganese(III) sulfate – red, manganese(III) acetate – brown 

Mercury: mercury(II) oxychloride – brown, potassium mercury(II) iodide – light yellow, copper(I) mercury(II) iodide – red or brown, mercury(II) sulfide – red or black, mercury(II) selenide – gray, mercury(II) iodide – red or yellow, mercury(II) oxide – orange

Molybdenum: molybdenum blue – blue or olive, molybdenum(II) chloride – yellow, molybdenum(III) chloride – red brown, molybdenum(III) hydroxide - greenish gray, molybdenum(V) chloride – blue black, molybdenum(III) bromide – black, potassium molybdenum(III) chloride – red, molybdenum(IV) oxide – brown or violet, Mo₄O₁₁ – violet, molybdenum(VI) oxide – white or bluish when cool and yellow when heated, molybdic acid – yellow crystals, molybdenum(IV) sulfide – blue gray, ammonium molybdenum(V) oxychloride – green, zinc molybdenum peroxo complex – red brown, molybdenum(VI) peroxo complex - yellow

Neodymium: neodymium(III) oxide – sky blue or pink or purple, neodymium(III) fluoride – lilac, neodymium(III) chloride solutions – rose pink or almost colorless, neodymium(III) bromide – green solid and dark brown liquid

Neon: See “Noble gases”.

Nickel: nickel – golden tinged gray, nickel(II) aqua solutions - green, nickel(II) chloro complex – yellow, nickel(II) ammine complex – blue, nickel(II) chloride – yellow green anhydrous and blue green hexahydrate, nickel(II) iodide - black anhydrous and blue green hydrate, nickel(II) oxide - green, nickel(III) oxide – black, nickel(II) thiocyanate – brown, potassium nickel(II) cyanide - orange

Niobium: niobium(V) chloride – yellow, niobium(II) chloride – brown, niobium(III) chloride – green black, niobium(IV) chloride – brown black, niobium(V) bromide – red, niobium(IV) iodide – dark gray, niobium(II) iodide – gray black, niobium(V) oxide – white when cool and yellow when heated, niobium(V) peroxo complex - yellow

Nitrogen: nitrogen dioxide – brown gas, nitric oxide –colorless gas and blue liquid, dinitrogen trioxide – blue liquid, nitrogen triiodide – dark brown powder, nitrosyl chloride – orange gas, lithium nitride – ruby red

Noble gases: The noble gases are colorless.

Osmium: osmium(IV) chloride – red brown or black, ammonium osmium(IV) chloride – dark red, osmium(IV) oxide – black, potassium osmate(VI) – pale violet red

Oxygen: dioxygen difluoride – brown gas, red liquid, ozone – light bluish gas, hydrogen peroxide- very pale bluish liquid, lithium and sodium peroxides - yellowish

Palladium: palladium(II) chloride – red brown solid and brown solution, palladium(II) oxide – black, potassium palladium(II) chloride – dark yellow or brown, ammonium palladium(II) chloride – olive green, palladium(IV) chloride complex – bright red, potassium palladium(IV) chloride - orange, palladium(II) ammine complexes – red or yellow, palladium(IV) oxide - dark red

Phosphorus: phosphorus – yellowish, red brown, or violet, diphosphorus tetraiodide – red, phosphorus trisulfide - yellow brown, phosphorus triselenide - orange, phosphorus pentabromide - yellow

Platinum: platinum(IV) chloride – reddish brown, platinum(III) chloride – dark green, platinum(II) chloride – greenish brown, chloroplatinic(IV) acid – orange, chloroplatinic(II) acid solution – red, potassium platinum(IV) chloride – yellow, potassium platinum(II) chloride – red, platinum(II) oxide – black, platinum(IV) oxide – yellow, potassium platinum(II) cyanide – blue or yellow, platinum(II) ammine complex – dark colored or yellow

Potassium: See “Alkali metals”.

Praseodymium: Praseodymium(III) chloride – bluish green when anhydrous and green when heptahydrated, praseodymium(III) fluoride – green, praseodymium(IV) oxide - black (top center), praseodymium(III) oxide - light green

Rare earth metals: Lanthanum, yttrium, lutetium, gadolinium, and ytterbium have no visible color in the majority of their compounds.

Rhenium: rhenium(III) chloride – red purple, rhenium(V) chloride – black brown, rhenium(IV) chloride complex – yellow green, rhenium(VI) oxychloride – red brown, rhenium(IV) oxide – gray black, rhenium(VI) oxide – red, rhenium(VII) oxide – bright yellow, sodium rhenite(IV) – brown, barium rhenate(VI) – green, rhenium(IV) sulfide – black, rhenium(VII) sulfide – black

Rhodium: rhodium(III) chloride – yellow HCl solution or red solid, rhodium(III) oxide – lemon yellow, rhodium(III) sulfate – red or yellow , rhodium(II) sulfate - red

Rubidium: See “Alkali metals”.

Ruthenium: ruthenium(IV) oxychloride – dark brown, ruthenium(III) chloride – yellow brown solution, ruthenium(IV) oxide – dark gray, ruthenium(IV) chloride complex – orange brown, ruthenium(VIII) oxide – yellow solid or solution and orange liquid,  ruthenate - red, potassium perruthenate – black solid and green solution, ruthenium(II) - lavender

Samarium: samarium(III) oxide – light yellow, samarium(III) sulfate – yellow, samarium(III) iodide – orange, samarium(II) iodide – yellow with brown solution

Scandium: Scandium iodide – yellow (in light bulb core), scandium sulfide – yellow

Selenium: selenium – red or purplish gray or black, diselenium dichloride – dark red  liquid, selenium tetrachloride – faint yellow, ammonium selenium chloride – yellow, diselenium dibromide – black liquid, selenium tetrabromide – yellow, selenium oxychloride – yellow liquid, selenium sulfur trioxide – dark green, selenium nitride – orange

Silicon: Silicon – bluish, silicon tetraiodide - yellow liquid, colorless solid

Silver: silver(I) oxide – dark brown, silver(I) carbonate – light yellowish, silver(I) iodide – light yellowish, silver(I) sulfide – black, silver(II) oxide – grayish, sodium argentite – light green, silver nitride – black

Sodium: See “Alkali metals”.

Strontium: See “Alkaline earth metals”.

Sulfur: Sulfur - yellow solid and red when molten, sulfur dichloride – red liquid, disulfur dibromide - red liquid, disulfur dichloride - yellow liquid, disulfur trioxide – greenish, thionyl bromide - yellow liquid, sulfur nitrides – yellow orange. Alkali metal sulfides turn yellow upon exposure to air.

Tantalum: tantalum(IV) chloride – brown, tantalum(IV)  bromide – black, tantalum(V) bromide – yellow, tantalum(V) iodide – black

Tellurium: potassium telluride – pale yellow, chlorotellurate(IV) and bromotellurate(IV) - orange or yellow, iodotellurate(IV) – gray, tellurium(VI) oxide – yellow or gray, tellurium sulfur trioxide – brown

Terbium: Tb₄O₇ – dark brown, terbium solutions – pale pink

Thallium: thallium(I) fluoride – yellow, thallium(I) bromide – pale yellow green, thallium(I) iodide – yellow or red, thallium(III) bromide – light yellow, rubidium thallium(III) bromide – yellow, thallium(I) triiodide – black, thallium(I) oxide – black, thallium(I) hydroxide – yellow, thallium(III) oxide – black, thallium(I) sulfide – black

Thulium: thulium(III) chloride – green, thulium(III) oxide - green

Tin: tin(II) iodide – orange, tin(IV) iodide – orange, tin(II) oxide – black, tin(II) bromide – bright yellow, tin(II) sulfide – brown, tin(IV) sulfide – gold yellow

Titanium: Titanium peroxo complex – orange, titanium(II) halides – black, titanium(III) chloride – violet, titanium(III) bromide – bluish black, titanium(III) iodide – violet, titanium tetrabromide – yellow orange, titanium disulfide – yellow, titanium nitride - yellow brown, titanium(III) hydroxide - dark blue, titanium(III) fluoro complex - green

Tungsten: tungsten(V) chloride – black, tungsten(VI) chloride – blue black, tungsten(IV) oxide – brown, W₁₈O₄₉ – red or violet, tungsten blue – brown to blue to violet, tungsten(VI) oxide – yellow, tungsten oxytetrachloride – red, tungsten sulfide – blue gray, potassium tungsten(III) chloride – dark green

Vanadium: vanadium(II) solution – lavender, vanadium(II) hydroxide - black, vanadium(III) solution – light green blue, vanadium(III) hydroxide - green gray, vanadium(IV) hydroxide - gray, vanadate(IV) solution - red brown, vanadium(IV) chloride – reddish liquid, vanadium(II) bromide – reddish brown, vanadium(II) sulfate – reddish brown, vanadium(III) bromide – black with violet vapor, vanadium(II) iodide – violet, vanadium(III) iodide – brown, vanadium oxychlorides – brown or green or yellowish or orange, vanadyl sulfate – bright blue, vanadates – light yellow, vanadium(V) oxide – orange brown, vanadium(V) peroxo complex - yellow and purple

Xenon: See “Noble gases”. Some xenon compounds may be colorful.

Ytterbium: See “Rare earth metals”.

Yttrium: See “Rare earth metals”.

Zinc: zinc oxide – white when cold and yellow when strongly heated

Zirconium: zirconium tetraiodide – red brown

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

Iridium is one of the rarest and densest elements in the earth's crust. It is found in small concentrations in platinum ores and competes with osmium for position of densest element, the two's densities being extremely close (22.56 grams per cubic centimeter for iridium, compared with 22.59 for osmium). Iridium's is named after the "goddess of the rainbow" because of the many colors that it exhibits in its salts. Meteorites tend to contain larger quantities of iridium than the general earth. Iridium does not dissolve in any acids, but is attacked by halogens and some molten salts when heated to a high temperature. Iridium black is an extremely black pigment for ceramics made of finely divided iridium metal. See this link for more information about the colorfulness of iridium chloride and its complexes.

In element form: Iridium spark plugs often contain pure iridium or iridium-platinum alloys plated on the central electrodes. Osmiridium pen tips for expensive pens contain iridium metal.

In compound form: No sources found.

Here is my sample of iridium. It is a spark plug with the electrode coated with a platinum-iridium alloy (90% Pt 10% Ir is typical).