40 Fun Facts About Barium

Barium compounds are packed into fireworks to make them burn with which bright color?

Green is barium's signature flame color, so reliable that chemists use it as a quick test for the element in an unknown sample.

Which nut, also famous for its high selenium content, naturally contains small amounts of the metal barium?

Brazil nut kernels carry traces of barium, but the amount is far too small to cause any of the sickness that larger doses of the metal bring on.

Patients swallow a barium sulfate drink, nicknamed a barium meal, so their gut shows on which medical scan?

X-ray beams cannot pass through barium sulfate, so the coated esophagus and stomach stand out clearly on the finished image.

Barium takes its name from the ancient Greek word barys, which has which meaning?

Heavy describes barium's ores rather than the metal: barite is so dense for a rock that miners knew it as heavy spar.

Marie and Pierre Curie discovered which glowing radioactive element hiding alongside barium in uranium ore?

Radium behaves so much like barium, its neighbor in the periodic table, that separating the two in the ore proved very difficult.

Otto Hahn's 1938 discovery of barium in uranium bombarded with neutrons was the first proof of which process?

Nuclear fission was the only way to explain it: barium atoms are about 40% lighter than uranium, so the uranium nucleus had to have split apart.

Alchemists prized barium-rich pebbles that glowed after exposure to light, found near which Italian city?

Bologna gave the glowing pebbles their name, and the "Bologna stones" fascinated alchemists long before anyone knew the element inside them existed.

Traces of Han purple, an ancient synthetic barium pigment, survive at which famous Chinese site?

Terracotta Army figures were painted with Han purple bound in lacquer, a lavish expense for the tomb of the first emperor, Qin Shi Huang.

Which English chemist first isolated barium metal in 1808 by using electricity to split one of its compounds?

Humphry Davy also coined the name, adding the metallic ending "-ium" to baryta, an older word for one of the element's compounds.

Barium belongs to which family of the periodic table, alongside calcium and magnesium?

Alkaline earth metals fill group 2 of the table, and barium is the fifth of the six, soft and silvery but too reactive to occur pure in nature.

Most of the world's mined barite is ground up to weight the fluids used by which industry?

Oil drilling crews pump barite-laden mud down the hole because its sheer weight holds back high-pressure rock formations and helps prevent blowouts.

Benitoite, a rare blue barium gemstone, is the official state gem of which US state?

California is the only place gem-quality benitoite has ever been found, at a single mine near the San Benito River that gave the stone its name.

Baritosis is a benign condition in which barium compounds build up over years in which organs of exposed workers?

Lungs speckled with barium dust show dense spots on a chest radiograph, yet the condition is benign and the marks slowly fade once exposure stops.

Barium carbonate, poisonous when swallowed, has been sold as a bait to kill which household pests?

Rats and mice were the target because barium compounds that dissolve are poisonous, unlike the insoluble sulfate used in hospitals, which is nontoxic.

A barium swallow test checks the throat, while a barium enema is used to examine which organ?

Colon walls coated with barium sulfate show up in outline, though colonoscopy has become the preferred test because it can also take tissue samples.

Barium sits directly below which fellow group 2 metal, known for its crimson-red flame?

Strontium is slightly harder than barium and takes its name from Strontian, the Scottish village near which its ore was discovered.

Which of these everyday words comes from the same ancient Greek root as the name barium?

Baritone joins the Greek barys to tonos, meaning tone, which is how a deep male singing voice came to share a root with a metal.

Which two-letter symbol stands for barium on the periodic table, where it holds atomic number 56?

Ba is barium's symbol, while Br belongs to bromine, Bi to bismuth and Be to beryllium, three other elements that share its initial letter.

YBCO, a barium compound, was the first superconductor that works when chilled by which cheap liquefied gas?

Nitrogen boils at 77 kelvin, comfortably below the 93 kelvin at which YBCO starts superconducting, so labs no longer needed costly liquid helium.

Which chemist detected barium as a new element in the 1770s but never managed to isolate the metal?

Carl Scheele got no further than a barium compound, and the metal stayed locked away for more than 30 years until electricity could pull it free.

Vincenzo Casciarolo, who made barium-rich stones glow in the dark around 1602, earned his living in which trade?

Shoemaker by trade and alchemist by hobby, Casciarolo was trying to make gold when he heated barite with charcoal and got a glowing stone instead.

The barium mineral witherite honors William Withering, the doctor who pioneered which heart drug from foxglove?

Digitalis made Withering famous after he traced a folk cure for dropsy to the foxglove plant, and he also showed witherite was a mineral in its own right.

In the 1880s the Brin process used a barium compound to extract which gas from air for industry?

Oxygen was soaked up from air by the hot barium compound and then released again, a cycle that ran in a purpose-built factory from 1884.

Barium metal long served as a getter, a thin film deposited inside which electronic parts?

Vacuum tubes were given a quick flash of barium vapor, which condensed into a mirror-like film on the glass and kept soaking up stray gas.

Barium titanate rose to importance in World War II as a substitute for scarce mica in which electronic parts?

Capacitors made with barium titanate hold far more charge for their size, and the same ceramic is piezoelectric, so it has also been used in microphones.

Which physicist, working with her nephew Otto Frisch, explained why Otto Hahn found barium in bombarded uranium?

Lise Meitner got the news by letter while a refugee in Sweden, and although she supplied the physics, the Nobel Prize went to Hahn alone.

Barium stars are giants that picked up their extra barium from a companion that is now which type of star?

White dwarf companions are the burned-out remains of stars that once forged barium in their interiors and spilled it onto their neighbors.

Barium poisoning weakens muscles because barium ions block the cell channels that carry which mineral?

Potassium normally flows through pores in muscle cells, and barium ions jam those pores, which is why swallowing a soluble barium salt can cause paralysis.

Rose rock, a flower-shaped cluster of barite crystals and sand, is the official state rock of which US state?

Oklahoma adopted the rose rock in 1968, and its barite roses formed about 250 million years ago, when a shallow sea covered much of the state.

In 1818 Louis Thénard used a barium compound to make which bleach and antiseptic for the first time?

Hydrogen peroxide was a previously unknown compound when Thénard made it, and barium salts stayed an industrial route to it until better methods took over.

Barium compounds replaced which toxic metal in some optical glass, keeping the glass highly refractive?

Lead makes glass bend light strongly but also spreads its colors apart, while barium raises the refractive index without that extra dispersion.

Barium ferrite's resistance to heat and corrosion makes it a favored coating for which data storage medium?

Magnetic tape coated with barium ferrite keeps its data through temperature swings and damp, and the same compound sits in bank card stripes and loudspeakers.

Which German scientist, whose name lives on in a piece of lab equipment, used electrolysis to make pure barium?

Robert Bunsen split molten barium salts with an electric current, and his laboratory also perfected the gas burner that still carries his name.

Baratol, an explosive blend of TNT and barium nitrate, helped trigger which atomic bomb dropped in 1945?

Fat Man used Baratol as the slow-detonating part of its explosive lenses, the shaped charges that focus the blast inward in an implosion bomb.

Which element, widely used in atomic clocks, sits immediately before barium in the periodic table?

Cesium holds atomic number 55, one below barium's 56, and it melts at just 28.5 °C, so it can turn liquid on a warm day.

A thin barium sulfate layer called baryta brightens the surface of which traditional printing material?

Photo paper gets its baryta layer before the light-sensitive emulsion goes on, which keeps the emulsion out of the paper fibers and gives more even blacks.

Mixing barium hydroxide with an ammonium salt is a classic classroom demo because the reaction can do what?

It can freeze water because the reaction is strongly endothermic, soaking up heat from its surroundings as two dry solids turn into a cold liquid.

Which physicist made a famous 1895 discovery after noticing a barium-coated screen glowing in his darkened lab?

Wilhelm Röntgen went on to see the first radiographic image, his own ghostly skeleton, flickering on that same barium platinocyanide screen.

A barium compound helps set off the thermite reaction used to weld which kind of steel structure on site?

Rail tracks are joined by pouring in molten iron from a thermite charge, and the same barium compound also works as a bleaching agent.

An alloy of barium and nickel is used in which car engine component?

Spark plugs are one of the few jobs for barium metal itself, since the pure element has few industrial uses and most barium is sold as compounds.