Molecular Monday: The Four Elements

September 18, 2017

For some reason, I’ve been thinking a lot lately about the original elements, the four elements Aristotle wrote about many millennia ago: fire, water, wind, and earth. Of course we no longer think of these as elements in the chemical sense. Instead we have the periodic table of elements, with well over a hundred elements identified so far.

But just for fun, I thought I’d try to find a way to connect the old Aristotelian elements to the first four modern chemical elements: hydrogen, helium, lithium, and beryllium. Here’s what I came up with:

  • Hydrogen: Let’s start by associating hydrogen with “water.” The word hydrogen actually means “water maker.” It got its name because in 1783, Antoine Lavoisier demonstrated that the oxidation of hydrogen gas produced water (this experiment also proved that water is not elemental).
  • Helium: Helium was first detected in the solar spectrum in 1868 and was thus named after the Greek word for “sun.” The Sun is pretty fiery, so my first instinct was to make helium represent “fire.” But I’m going to go with “air” instead, because of helium’s use in balloons and airships.
  • Lithium: As I’ve written about previously, lithium was first discovered using a method called a flame test. When a chemical substance is burned, the color of the flame can be used to determine the chemical’s identity. Lithium burns with a characteristic bright crimson flame. Therefore, I’m choosing to associate lithium with “fire.”
  • Beryllium: Beryllium was first identified in 1798 as a component of the mineral beryl, specifically a form of green beryl we all know as an emerald. So I think I can safely wrap this little game up by connecting beryllium with “earth.”

So how did I do? Do you agree with the connections I came up with? Are there other connections we could think up that might work better?

Okay, maybe this was more of an exercise in creativity than science. I’m okay with that. And besides, in the half-hour I spent researching for this post, I learned a few things about the first four elements of the periodic table that I didn’t know before. That’s always a plus.

Anyway, next time on Molecular Monday, we’ll be talking about boron. Now I wonder if I can find some way to associate boron with the girl from The Fifth Element.


Molecular Monday: Lithium Brine

September 4, 2017

Welcome back to another edition of Molecular Mondays, a special biweekly series here on Planet Pailly combining two of my least favorite things: chemistry and Mondays.

These past few weeks, I’ve been reading a lot and learning a lot about lithium, because I’m a science fiction writer and I need to know stuff about this particular element for worldbuilding purposes. Except so far, I seem to be doing more world-destroying than worldbuilding.

Lithium is the kind of element that tends to form really strong chemical bonds—so strong that once lithium bonds to other elements, it can be really difficult to make it let go.

In fact Johan Arfwedson, the chemist who discovered lithium, was never able to isolate the element by itself. He could only infer its existence based on the unusually bright crimson color produced when a lithium-containing compound was burned (in other words, he was only able to identify it spectroscopically).

Given how hard it is to isolate lithium, I assumed lithium mining must be an arduous task. And it probably would be if we had to extract it directly from rock; but over three quarters of the world’s commercially available lithium does not come from rock. It comes from brine.

Pockets of water beneath the Earth’s surface can, over long periods of time, leech minerals like lithium out of the surrounding rock. The lithium intermingles with other elements in the water, creating lithium salts, and gradually as the water gets saltier and saltier it turns into lithium brine.

All we have to do is dredge that briny water up out of the ground, pour it into an artificial pool, and leave it out under strong sunlight. When the water part of the brine evaporates away, we’re left with lots and lots of lithium salts (and other kinds of salt too, but for our purposes we only care about the lithium salts). Apparently this is one of the easiest mining processes around, and also one of the least harmful to the environment.

I still have more research to do on this subject, but at least now I know my fictional lithium-rich moon would not necessarily burst into flames just because there’s water.


Molecular Monday: The Discovery of Lithium

August 21, 2017

Welcome back to another edition of Molecular Mondays, a special biweekly series here on Planet Pailly combining two of my least favorite things: chemistry and Mondays.

My current Sci-Fi work in progress is starting to turn into a bigger project than I originally anticipated, which means I need to learn more about lithium: the chemical element which I’ve unwisely scattered all over a certain alien moon.

Over the years, I’ve found that one of the best ways to learn about science (at least for me) is to take a historical approach. With that in mind, today I’d like to talk a little about the moment in history when lithium was first discovered.

It was 1817. Sweedish chemist Johan August Arfwedson was working in the laboratory of Jon Jakob Berzelius, on of the great “fathers of modern chemistry.”

Apparently it was common practice for chemists at that time (and also for chemists today) to light things on fire in order to see what color flames they’d get. Because different materials burn in different colors, the colors can tell you a great deal about what material you’re actually working with. Today this is known as a flame test.

Arfwedson was flame testing a kind of rock called petalite. When burned, petalite produced an intense crimson flame, like this:

Now when Arfwedson saw those bright crimson flames, he did not immediately conclude that he’d discovered a new element. Instead, he did what any good scientist would do: he thought up possible explanations for this crimson color and then systematically tested each possibility, ruling them out one by one.

In the end, Arfwedson was left with only one possibility: petalite must contain a previously unknown alkali metal. Arfwedson named this alkali metal lithium, after the Greek word for stone. “This name,” Berzelius, Arfwedson’s mentor, would later write, “recalls that it was discovered in the mineral kingdom, whereas the two others [sodium and potassium were the only other known alkali metals at the time] have their origin in the vegetable kingdom.”

At this point, you might be wondering what any of this has to do with my story. I’m kind of wondering that myself. Umm… I’ll get back to you about that. In the meantime, there are lots of other cool flame test videos to watch on YouTube.

Sources

Lithium from the Royal Society of Chemistry

Lithium from Elementymology & Elements Multidict

Alkali Metal from the Encyclopedia Britannica


Molecular Monday: Worldbuilding with Lithium

August 7, 2017

Once upon a time, long before I knew much about chemistry, I wrote a Sci-Fi story set on a moon orbiting some far-flung gas giant. For story reasons, I needed this moon to have some sort of valuable resource, and I picked lithium to be that resource. Again, I didn’t know much about chemistry at the time, but for some reason I guessed this lithium-rich moon would probably have a rust-red color to it, like Mars.

Fast forward to today. I’m currently in the process of revising this and other stories in the Tomorrow News Network series. One of the things I’m trying to do is apply a little more science to my storytelling. And regarding this rust-red moon, it turns out I sort of got this one right!

There is a compound of lithium and nitrogen called lithium nitride (chemical formula Li3N) which has the kind of dark red color that I wanted for my moon. Lithium nitride forms spontaneously wherever pure lithium comes into contact with atmospheric nitrogen, so it’s fairly easy to make. It doesn’t seem like much of a stretch to me that a lithium-rich moon would be covered in this stuff.

Of course the characters in my story need an otherwise Earth-like environment. That means Earth-like gravity, free oxygen, an active water cycle…

Okay, I’m not clear on just how rapidly everything would catch on fire in this situation, but based on a YouTube demonstration and some lab safety info I found online, it seems you should be careful about exposing lithium nitride to oxygen, and for God’s sake keep it away from water!

So yeah… it seems I have some to rethinking to do. Fortunately, there are other, less explosive lithium compounds I could work with.

Programming note: I’ve been doing Molecular Mondays as a once-per-month thing for a while now, but I feel like I’m starting to slip with my chemistry research. So Molecular Mondays will now return to its original biweekly schedule. So tune in two weeks from today when we’ll be talking about… I don’t know, probably lithium again.


Molecular Monday: Water Gets Freaky

July 3, 2017

After today’s post, you might never look at a glass of water the same way again.

The water molecule is made of two hydrogen atoms plus one oxygen atom, arranged in a Mickey Mouse shape, with the chemical formula H20. You already knew that, I’m sure. But you may not be aware of this: water’s chemical formula gives you a hint about water’s true nature.

Hydrogen ions play an important role in acid/base chemistry, so when you see hydrogen listed first in a chemical formula, that typically indicates that you’re looking at the chemical formula of an acid.

  • Acid: an acid is a chemical that can give up a proton (a.k.a. a hydrogen ion) to a base.
  • Base: a base is a chemical that can accept a proton from an acid.

Water can do both. It’s an acid. It’s also a base.

  • Acidic Water: a water molecule (H2O) can give up a proton to a base, transforming itself into a hydroxide ion (HO).
  • Basic Water: a water molecule (H2O) can accept a proton from an acid, transforming into a molecule called hydronium (H3O+).

Now this is where things get really freaky: because water is both an acid and a base, it can actually react with itself.

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Image credit: Manuel Almagro Rivas – Own work, CC BY-SA 4.0, Link

In fact water is constantly reacting with itself. The result is that even “pure water” is really a mix of water, hydroxide, and hydronium in a proton-swapping party that never ends.

Something to think about the next time you drink a glass of water.

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Today’s post is part of a special series here on Planet Pailly called Molecular Mondays.

On the first Monday of the month, we take a closer look at the atoms and molecules that make up our physical universe, both in reality and in science fiction.


Where Does Fat Go When You Exercise? (A Molecular Monday Post)

June 5, 2017

Exercise is good for you, I guess. It’s probably one of the better options for anyone who’s trying to lose weight. But when you exercise, where does the weight go, physically speaking?

The first time someone asked me this question, my best guess was that it had something to do with Einstein’s E = mc2 equation, the equation that allows matter to be converted into energy. But I knew that couldn’t be right. That’s more of a nuclear physics thing, and the human body is not a nuclear reactor.

The actual answer has to do with chemistry. Rather simple chemistry. This is a triglyceride molecule:

Okay, it is sort of a complicated-looking molecule. Don’t worry. Your body knows what to do with it, even if your brain doesn’t.

The important thing, in relation to today’s question, is that triglyceride is composed almost entirely out of carbon and hydrogen atoms, with a few oxygen atoms sprinkled in.

Now when your body exposes triglyceride to the oxygen you breathe in, that highly reactive oxygen starts breaking the triglyceride molecule apart. With each chemical bond that breaks, a little bit of energy is released (allowing you to keep exercising), and the broken pieces of triglyceride recombine with oxygen to make carbon dioxide (CO2) and water (H20).

It’s worth noting that chemical bonds do contribute marginally to the total mass of a molecule, so when you break them and turn them into energy, E = mc2 does apply, sort of. But that’s nowhere close to being a significant factor in terms of weight loss.

The vast majority of the weight you lose comes in the form of carbon dioxide, which you breathe out through your lungs, and water, which you sweat out or pee out or breathe out as water vapor. (If you want to get into the math and find out how many kilograms of oxygen you need to burn how many kilograms of triglyceride, producing how many kilograms of water and CO2, click here.)

When I started studying chemistry, this was not the kind of thing I was hoping to learn. I’m a science fiction writer. I’m interested in the type of chemistry that makes rocket engines go, or drives weather patterns on other worlds, or could make alien life possible.

But still, it’s exciting to me when I can connect all that outer space science to some of the mundane aspects of life here on Earth.

* * *

Today’s post is part of a special series here on Planet Pailly called Molecular Mondays.

On the first Monday of the month, we take a closer look at the atoms and molecules that make up our physical universe, both in reality and in science fiction.


Molecular Monday: Why Chemistry?

May 1, 2017

The first Monday of the month is Molecular Monday here on Planet Pailly!

We just wrapped up this year’s A to Z Challenge, and I ended up writing a lot about chemistry. A lot more than I expected. You’d think I must really love chemistry.

But I don’t.

I really don’t.

For a long time, I tried to avoid the subject completely due to bad memories from high school chemistry. My professor was extremely generous in giving me a just-barely-passing grade.

So when I made the commitment to include more science in my science fiction, I figured I could get by with just the “fun” sciences like physics and astronomy. Then in 2015, I did my yearlong Mission to the Solar System, and the planet Venus forced me to start learning this chemistry stuff.

As you can see in this totally legit actual Hubble image, Venus has some very special chemical activity going on.

There’s simply no way to understand what’s happening on Venus without getting into the weird sulfur chemistry of the Venusian atmosphere. But once you do make sense of that sulfur chemistry, a strange new world is suddenly open to you: a world of both heavenly beauty and acid rain hellfire death.

Since my experiences with Venus, I’ve come to realize that understanding chemistry, even at a basic level, makes my work as a science blogger and science fiction writer so much easier.

  • Is there life on Mars or Europa? What about life in other star systems, or silicon-based life? If alien life is out there, it will be the product of chemistry.
  • What about humans traveling to other worlds? What would be safe for us to eat or breathe? Chemistry can help answer that too.
  • Venus isn’t the only world defined by chemistry. Earth has been shaped in large part by the chemistry of oxygen and water; the gas giants by ammonia and methane; and then there’s a true oddball like Titan with its tholen chemistry.
  • And how am I going to get my rocket ship off the ground? By mixing rocket fuel. In other words, by doing chemistry.

Chemistry is by no means the most fundamental science, but for the kinds of things I write, it is the most applicable science. So even though I don’t enjoy the subject, I’ve forced myself to stick with it.

And if I’m being perfectly honest, in those aha-moments when complex chemical reactions suddenly makes sense to me, I may quietly murmur to myself, “Okay, chemistry is kind of fun.”