The Language of Chemistry

Original

Beginning students of chemistry encounter chemical symbols which bear little resemblance to their English names. The roots of several common and especially more historical elements caught my fancy, just as other Latin words buried in English did earlier. link

Several names and symbols come from Latin:

• Sb stands for antimony which comes from the Latin Stibium. The Italians still call antimony stibio. We did too until the Middle Ages. link

• Cu for copper comes from Cuprum, which is related to the word Cyprus, an ancient source of copper for the Romans.

• Fe for iron comes from Ferrum. The Italians call their railroads la ferrovia and Spanish calls hardware ferreteria (cf. bilingual signs at Home Depot). English has the vestigial word, farrier.

• Au for gold comes from Aurum.  We've lost that word in English except for some pretentious words like aureate, aurelia, aureole and the like.

• Pb for lead comes from Plumbum. There are lots of English cognates, including plumbago, plumbing, plumb lines and plumb bobs.

• Hg for mercury comes from hydrargyrum. That's confusing because at first glance it could be water-silver. But "hydra" is more generic and means liquid. Mercury used to be called quicksilver which sort of conveys the same notion as hydrargyrum.

• Ag for silver comes from Argentum. The French still call money l'argent.

A couple names look like Latin but are neologisms coined by Sir Humphry Davy:

• K for potassium comes from Kalium which derives from Arabic al-kali.

• Na for sodium comes from Natrium. The Germans still use both words Natrium and Kalium; they never adopted sodium and potassium. I guess they weren't as impressed with Davy as we were.

Also:

• Sn for tin comes from the Latin Stannum. There is some irony here.  The word Stannum is Latin but appears to derive from Irish or Welsh. The Romans got their tin from the British Isles.  Tin is still mined in Cornwall.

• W for Tungsten comes from an older name, Wolfram, which is still used by the Germans. Tungsten derives from Swedish tung heavy + sten stone. 

It's No Lye That Soap Is Made From Pot Ash

The word potassium came from the Dutch word "potash" literally referring to the substance left behind in the kettle or pot when wood ashes are leached with water and then left to evaporate--whence my title [insert snickering reference to the Dutch and their penchant for "pot"].

Scooping the ash out of the fireplace reminded me of how people used to make their own soap from lard. The first step in making soap is to have a good quantity of lye on hand. Lye is just concentrated potassium hydroxide, KOH, easily made from wood ash. recipe  Someone I knew back in Wisconsin used to make his own soap from used motor oil. The stuff worked quite well and really cut grease, but it smelled a bit like...used motor oil.

Potassium (but not sodium) is essential to plants and the growth of wild plants is often limited by their supply of K⁺.  This is also why fertilizer is classed according to its nitrogen-phosphorus-potassium (NPK) content. Plants don't have feelings and the proof is that they don't require the sodium crucial for propagating nerve impulses. I found a cool animation of how potassium and sodium are channeled and gated here. Back in my day we had no such animation tools and we had to imagine concepts like this. Here is a complete animated overview of how our brains communicate with our toes: link. Sodium and potassium are crucial for these processes.

In a way, this also describes how words become flesh.

Natrium Facit Saltus

Metallic sodium is hot stuff.  It's sold in chunks or slabs immersed in oil to protect it from air and moisture.  I used to play around with it in the lab. I'd cut up chunks with a spatula (butter knife) and weigh it out for various uses.  It was always fun to toss any excess into a bucket of water and watch it sputter and bluster, forming itself into a smaller and smaller ball as it skittered across the surface, held aloft by the hydrogen gas it was forming. Sometimes it would even catch fire.  Here is a video showing this: link.

The thing about sodium is that it is so ubiquitous.  Universally, not just terrestrially. Unlike plants, we humans need sodium, yet nowhere near as much as we get. The whole "salt" debate is controversial. For leading links, check out the comment section in the following link.

Lesser known about sodium is that it gives us a pretty peach color which we associate with fire. But not the fire of the sun.  The orange blaze of the sun is really white light filtered by our atmosphere and lacks the orange color of sodium. Let me explain.

The sun floods us with a spectrum of visible light.  Here is the solar spectrum sorted according to ROY G. BIV wavelength:

Missing from the solar spectrum are several well known "lines" having alphabetical designations. These Fraunhofer lines were discovered in the 19th century by early German spectroscopists who first analyzed sunlight.  The black bands are "missing" wavelengths caused by the absorption of those colors by different chemical elements present in the outermost regions of the sun. Sodium in the sun causes the pair of lines labeled "D" in the solar spectrum. We don't notice that the lines or specific colors are missing from sunlight because our eyes aren't able to distinguish a missing wavelength, especially when surrounded by others (especially ones close in wavelength).

Here on earth, sodium in flames gives an intense orange glow which is the exact color missing from sunlight. Try sprinkling a little salt on an open flame sometime--you should see an intense light that looks like this:

The sodium spectrum above reminds me of an old-fashioned AM/FM radio dial found in 20th century automobiles and stereo systems. Sheesh I'm getting old fast.
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When I was researching this blog post, I kept running across articles which ascribed the color of campfires and the like to the intense color of sodium. I thought this was odd because plants for the most part do not require sodium, so any sodium present in wood must be adventitious and probably sequestered away.  It turns out that the common orange color seen in burning wood is partially due to residual sodium, but mostly comes from luminescent soot particles, a phenomenon first explained by Michael Faraday (link).