Correcting A Misconception

A recent article in Science dismayed me. The authors wrote one of those "perspectives" articles describing the gist of one of the real peer-reviewed research articles later on in the magazine.

"Getting Moore from Solar Cells" by David J. Norris and Eray S. Aydil, Science 2012, 238, 625.

After describing some new and interesting materials for solar cells, the authors state:

"Although this sounds exotic, these materials are known to behave like semiconductors, allowing them to absorb the sunlight and create electrons"

At the risk of sounding pedantic, electrons are not created--nor are they destroyed. They are there in the dark in the beginning, and they are still there after the lights go out.  The electrons are merely excited by the light.

Photons knock up electrons and then leave the seen.

All According To A Nefarious Plan

This struck me as odd too last night:

So Obama thinks high gas prices are due to a vigorous, recovering economy that’s supposedly no longer on the “verge of collapse”?   There are so many fundamental errors in basic economics that it almost leaves one speechless. link

Of course, it's all according to plan: another link

My wife suggested that oil companies might be colluding to raise prices in California in order to help Romney.  I reassured her that Dianne Feinstein was already on the case.

You Wanna Picture Or 1000 Words?

This is part of the problem, not the solution:

Of course, it's all according to plan. Link

The First Quantum Mechanic

Max Planck was the first quantum mechanic.  He began as an "old school" mechanic, thoroughly steeped in Newtonian mechanics and Maxwell's electrodynamics; those laws conveniently sorted physics into the "corpuscular" and the "ethereal" domains, a dichotomy that corresponded to things having mass and things lacking mass, i.e., radiant light. Higgs had something to say about this later.

Isaac Newton had solved the age-old riddle of why apples fall, allowing astronomers to predict the motions of the heavens. Miracle, mystery and authority. Newton also dabbled in light, describing reflection and interference--along with his famous prism experiments--but the mathematical laws governing light propagating "through the ether" were first described by a Scotsman, James Clerk Maxwell. Newton's Laws of Gravitation governed masses while Maxwell's electrodynamics ruled the waves. Planck came along in 1900 and sort of melded the two theories at their interface.

Physics then had a big unsolved problem called "black body radiation." Heating kilns and ovens made the inside walls glow--first red, then yellow, and finally white hot. Glass makers and potters could even gauge an oven's temperature based on its color inside. Adding more heat to an oven made the walls give off progressively higher energy light but there was a limit: ovens would not begin to emit UV light. Light bulbs were another 19th century invention that used heat (electrical resistance) to produce light and Planck was motivated in part by practical concerns.

What Planck did can be summarized visually with a plot of light intensity versus wavelength:

Planck's theoretical curves (berechnet) agreed beautifully with experiment (beobachtet). Note that there are seven different non-overlapping curves corresponding to progressively higher temperatures. Prior attempts to predict the same phenomenon, based on classical electrodynamics, had failed. These attempts are neatly summarized in this graphic:

The green line corresponds to Planck's law and to reality; the red line, Rayleigh-Jeans Law, only worked at low frequencies (long wavelengths), while the blue line, Wien's Law, worked only at the high frequencies (short wavelengths).  As an aside, the red line's straight up ascent was later referred to as the "Ultraviolet Catastrophe" as a sort of metaphor for the failure of classical theory to account for the reality of Planck's Law. But Planck did more than meld two theories--he invented anew.

The newer science of thermodynamics and Maxwell Boltzmann in particular had shown that tiny invisible yet indivisible atoms could statistically sum to bulk properties. The details are grounded in probabilities rather than certainties, much like my Parable Of The Gas. What Planck did was to apply Boltzmann-like statistical mechanics to the problem of black body radiation.

Planck viewed a red-hot oven (black body radiator) as material in equilibrium with light--sort of a transubstantiation of the ethereal and corpuscular. He named the nexus--the unseen--"resonators" and counted them in a statistical way, describing their behavior mathematically. This was all well before anyone knew or even thought that atoms were held together by electrons--atoms were still thought to be amorphous blobs. That something as seemingly seamless as light should be treated like discrete masses when it interacted with matter was an assumption but it proved key to deriving the solution to the black body problem. There was no other way to explain the behavior. What Planck did was revolutionary, but he did not do it because he understood why--he did it because his theory fit experiment. Werner Heisenberg later stated Planck's insight most succinctly and in most certain terms:

Radiant heat is not a continuous flow and indefinitely divisible. It must be defined as a discontinuous mass made up of units all of which are similar to one another. 

Around the time of Planck's insight, another, younger German physicist appeared on stage. He was then a Swiss patent examiner and barely known, preoccupied with developing his own theories of relativity, but his elastic mind intuitively wrapped around what even Planck had trouble fully accepting and generalizing.  Einstein took Planck's teachings and explained the photoelectric effect--why blue light but not red light could make certain metals conduct electricity. It seemed counter intuitive that even the most intense red light could not do what the faintest of blue light could do. Einstein explained that only blue light was energetic enough to knock electrons free. There were energy thresholds and band gaps at the atomic level. Discontinuities and E=hv.

According to Thomas Kuhn, Planck needed the goading of Einstein and Paul Ehrenfast afterwards to fully realize what he had done. Certainly Planck's older contemporaries were doubters too. In Planck's words:

A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

Planck and Einstein remained close friends throughout the 1930's. Planck, conservative Christian, and Einstein, agnostic Jew, enjoyed making music together when not discussing physics in Wilhelmine and Weimar Berlin--while it lasted (maybe they did discuss the physics of music--frequencies, harmonics, metered beats). Planck tried in vain to intervene on his friend's behalf during the rise of the Nazi regime but he ultimately failed.

There was even greater sadness for Planck besides the exile of his great friend Einstein; there was the trial of his eldest son Erwin at the hands of Roland Freisler, whom I described back here. The Nazis executed Erwin Planck just a few heartbreaking months before the whole regime finally collapsed. The older Planck never recovered from the loss of Erwin and died just two years later in 1947. Here they are during happier times:

Max and son Erwin Planck

Erwin Planck on trial for his life before the People's Court, arrested and charged as part of the July conspiracy to assassinate Hitler:

Erwin Planck vor dem Gesezt in 1945

Erwin Planck, like so many others, was only involved in aftermath planning--helping to draft a post-Hitler German Constitution--and not the actual assassination plot.

The elder Planck's life sort of tracked a shape: A half-century of slow triumph peaked in the 1930's and then precipitously declined, much like the shape of one of his triumphant black body radiation curves which conquered physics. Post-war Germany honored Planck by renaming the Kaiser-Wilhelm-Gesellschaft (its premier scientific society) the Max-Planck-Gesellschaft.

Parable Of The Gas Explained

A while back I wrote The Parable Of The Gas without explanation:

Consider a spherical, sealed glass container of gas. Further suppose that the gas inside is all the same -like helium in a balloon. Room temperature and stable. Everything equal inside...but it's not. The individual gas atoms in the container have unequal energies because there's a range--a statistical distribution--of energies present: Some atoms move more slowly than others, some more quickly, some much more quickly.

How can we make things fair? How can we make it such that each individual (atom) has the same energy as its next nearest neighbor? We cannot. The only way to approach that state is to remove energy from the entire system. Cool the economy. Everything slows. Eventually, approaching zero Kelvin, all motion stops. Of course catastrophic things like condensation (downsizing from gas to liquid) and solidification (loss of liquidity) occur along the way. But the goal is achieved: every atom is finally the same (or nearly the same) energy wise.

Here is what I was picturing:

Original

The figure shows how at higher temperatures the average speed increases but so does the spread (inequality). The range narrows at lower temperatures which is what some policymakers seem to want. But what they want is also unnatural and contrived. An Austrian physicist named Ludwig Boltzmann first came up with the mathematical model behind all this in 1877. He based his derivation on entropy--arguing that a situation where all members of a group have identically the same velocity is highly improbable--as improbable as all the gas molecules being located on just one side of the vessel. It's much more probable (favorable) to allow each member of the group to experience a range of velocities and not to constrain them into one single energy or spatial configuration.

Another physicist named Max Planck extended Boltzmann's ideas and also changed the world by extending statistical mechanics to heat and light thus introducing quantum mechanics.  Einstein ran even further with Planck's ideas.  Both men would have their doubts--"God doesn't roll dice" and all that--but neither man denied reality.

Added:  When I liken the economics of wealth and poverty to a gas, it's important to remember that "rich" and "poor" may interconvert: link

Rumford, Soddy, and The Crash

Frederick Soddy (1877-1956)

Despite years of formal education in chemistry, I'd never really heard of Frederick Soddy until I started reading about the early days of radioactivity. He wrote a book called The Interpretation Of Radium (1909) which is available free online here.  The book so influenced H.G. Wells that he dedicated his book, The World Set Free (1914), to Soddy.

Soddy seems to have had two careers--first as an accomplished physical scientist (Chemistry Nobel in 1921) and then as a sort of social scientist, but more accurately as a social activist during the Great Depression. In this way he was a prototype Linus Pauling, who won both a Chemistry Nobel and a Peace Nobel for his activism.

Soddy was a chemist by training but today he'd be called a radiochemist. He must have seen or heard firsthand many of the key discoveries in nuclear physics in the late 19th and early 20th century, first at Oxford and then as graduate student with Lord Rayleigh. Afterwards, Soddy moved to Canada around the same time Ernest Rutherford did and the two joined forces. Together they discovered the natural transmutation of elements. Soddy's Nobel Prize citation reads:

for his contributions to our knowledge of the chemistry of radioactive substances and his investigations into the origin and nature of isotopes.

His isotope work came later.

Recall that Count Rumford first paid attention to the heat given off boring cannon and thereby converted our notions of energy.  Like Rumford, Soddy first realized how much heat and energy radioactive decay gave off--orders of magnitude more energy than burning fossil fuels did and it was also seemingly inexhaustible. Soddy was so prescient regarding how much energy was locked inside uranium, radium, and thorium that he warned Britain's government about the dangers of "atomic" bombs during the First World War.

The notion of cheap and abundant atomic energy crested in 1954 with Lewis Strauss' famous too cheap to meter statement, though it appears that he was referring to hypothetical hydrogen fusion reactors.

Soddy died in 1956 in relative obscurity. This (from the Wiki bio) is intriguing:

In four books written from 1921 to 1934, Soddy carried on a 'quixotic campaign for a radical restructuring of global monetary relationships', offering a perspective on economics rooted in physics—the laws of thermodynamics, in particular—and was 'roundly dismissed as a crank'. While most of his proposals - 'to abandon the gold standard, let international exchange rates float, use federal surpluses and deficits as macroeconomic policy tools that could counter cyclical trends, and establish bureaus of economic statistics (including a consumer price index) in order to facilitate this effort' - are now conventional practice, his critique of fractional-reserve banking still 'remains outside the bounds of conventional wisdom'. Soddy wrote that financial debts grew exponentially at compound interest but the real economy was based on exhaustible stocks of fossil fuels. Energy obtained from the fossil fuels could not be used again. This criticism of economic growth is echoed by his intellectual heirs in the now emergent field of ecological economics.

Ignore The Skidmarks

Thirty years ago and I still recall a problem on a physics final exam at UW-Madison. It went something like this:

A tire is rolling at a constant speed along a pavement. A brake is suddenly applied, bringing the tire to a screeching halt. If the initial temperature of the tire is T_o, what is the final temperature of the tire? You may ignore heat exchange between the tire and road. 

The solution required a couple more pieces of info like the tire's velocity and mass, as well as the heat capacity of the tire.  I omitted those details. I remembered the problem because it was such a nice example of the first and second laws of thermodynamics.

First--all of the kinetic energy (called angular momentum) of the rolling tire changes into thermal energy (heat) as the tire skids to a halt. Nothing is "lost." The rubber in the tire heats up accordingly.*

Second--entropy increases for the energy transformation, meaning that all the well-ordered motion of the rolling tire transforms into the chaotic thermal vibrations of the warmer tire. The second law says that the reverse will not occur. In other words, a rolling tire can suddenly stop and heat up, but heating a tire will never make it roll.
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James Joule spent part of his honeymoon in Switzerland measuring temperature differences between the tops and bottoms of waterfalls. His hypothesis was that the water should be warmer after the kinetic energy of the falling water is converted into heat. There were no forthcoming reports of frictional experiments with his bride.

Boredom Creates Friction

Count Rumford (1753-1814)

Benjamin Thompson (born in Woburn, MA) was the American anti-Franklin. He was a prolific inventor and scientist but sided with Britain during the Revolution and left America after the War and lived abroad thereafter. He eventually settled in Bavaria where he changed his name to Count Rumford and then changed our understanding of the science of heat. And he did all this in the service of practical pursuits.

Rumford oversaw the boring of iron cannon from iron cylinders using a horse-driven drill. He was impressed by how much heat the drilling friction gave off and he designed experiments to measure this. With insulated cannons and submerged drilling experiments, he carefully measured temperature increases. He found that sustained drilling could heat and boil cold water! Collecting and weighing the iron filings, he established that the metal shavings had the same weight and properties as the unbored metal, so nothing had been "given off" as was then currently thought. Rumford concluded that the mechanical work by the horses was converted into heat. Rumford showed that mechanical action can generate indefinitely large amounts of heat, thus directly challenging the caloric theory of the great Frenchman, Lavoisier. 

Lavoisier, a contemporary, didn't live to appreciate Rumford's work--he was guillotined in the French Revolution--ironically for Royalist sympathies. Rumford wound up marrying his widow, Marie-Anne Paulze who was an unappreciated chemist in her own right.

Entropy Machinations

Entropy* is a difficult concept to grasp. It's like the silent chaos created when ice melts to water. The crystalline phase disappears; internally, frustrated solid-phase lattice vibrations silently convert into liquid liquid-phase translations and rotations; degrees of freedom are conserved but increase their measure. Proton transfer becomes possible. And yet nothing has changed chemically because ice is still water except in degree. Entropy increased. Disorder ensued.

Entropy can also decrease--enzymes do this unto entropy all the time as does anything which expends energy ordering things around. This video animates making order out of chaos--decreasing entropy: the red and green blocks sort themselves and separate. The ordering happens because the red blocks differ slightly from the green blocks and fit together better.

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*entropy
1868, from Ger. Entropie "measure of the disorder of a system," coined 1865 (on analogy of Energie) by German physicist Rudolph Clausius (1822-1888) from Gk. entropia "a turning toward," from en "in" (see en- (2)) + trope "a turning" (see trope). Related: Entropic.

Radiant Transfer

Photo taken tonight at the Oceanside Harbor beach at sunset:

OK, it's not the best quality, but it has all the classical elements: earth, wind, fire, and water.

The juxtaposition of the campfire and the sun reminded me of a conversation I had with my kids two years ago: link

Me:   Did you see that?  Where does that energy come from?

Son:   Hydrogen?

Me:    You think there's hydrogen inside the log?

Son:    No

Me:    What's in the log that burns?

Son:    Wood

Me:     Where does the wood come from?

Son:    The tree makes it

Me:     Where does the tree get energy?

Daughter:  From the sun!

Me:     Yes!

Son:     But isn't the sun hydrogen?

A Conservative Notion of Energy

Julius von Mayer (1814-1878)

The relation between food and work is intuitive: eat or die.* We also think that overeating can be offset by exercise and modern treadmills enable this thinking by showing us calories burned. And while the relation between food and work now seems intuitive, the equivalence of heat and work--or more precisely their interconversion--was a non obvious deduction.

Non obvious because work seems focused--while heat seems dispersed. It took centuries of sustained effort by thinkers and scientists to get us where we are today: that heat and work are equivalent and can interconvert.  Along the way, one man nearly took his own life for want of attention: Julius von Mayer.  His story involved blood, and indirectly, iron. To him we owe the First Law of Thermodynamics:

Energy can be neither created nor destroyed. It can only change forms

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*The German verb sterben, to die, is etymologically linked to our verb to starve.

The Very First Guinea Pig?

Commenter Ritmo's link to the wiki article about dioxin mentioned guinea pigs, which reminded me of Lavoisier, who may have been the first scientist to test theories using that animal. Lavoisier famously taught that combustion was the combining of oxygen with other elements, overthrowing the older notion of phlogiston which I wrote about here.

According to the OED of etymology, the first recorded use of the term guinea pig in a scientific context dates from the 1920s. However, the following description of the work of Lavoisier and Laplace clearly antedates that usage: link to original

Lavoisier's respiration experiments invalidated the phlogiston theory despite protestations from Priestley and Scheele. Lavoisier collaborated with French mathematician Pierre Simon de Laplace (1749 -1827) on problems in respiration chemistry. Their vital experiments with guinea pigs in 1780 first quantified the oxygen consumed and carbon dioxide produced by metabolism. Over a ten-hour period, they collected approximately 3 g of carbonic acid from an animal breathing oxygen. In a second experiment, they placed a guinea pig into a wire cage, which in turn was placed into a double-walled container. Ice packed into the double walls of the outer container maintained a constant temperature; ice between the cage and the inner wall of the container melted because of the animal's body heat. During 24 hours 13 oz. (370 g) of ice melted. Lavoisier and Laplace concluded that the total heat produced by the animal equaled the amount heat required to melt ice. In their own words:

Respiration is thus a very slow combustion phenomenon, very similar to that of coal; it is conducted inside the lungs, not giving off light, since the fire matter is absorbed by the humidity of the organs of the lungs. Heat developed by this combustion goes into the blood vessels which pass through the lungs and which subsequently flow into the entire animal body. Thus, air that we breathe is used to conserve our bodies in two fashions: it removes from the blood fixed air, which can be very harmful when abundant; and heat which enters our lungs from this phenomenon replaces the heat lost in the atmosphere and from surrounding bodies.
...animal heat conservation is thus largely attributable to heat produced by the combination of humid air inspired by the animals and dry air in the blood vessels.

Lavoisier's ideas were radical for 1780 because they connected heat, work, and energy.

Treat The Wealth Well

At the heart of Energy Secretary Chu's newly released Strategic Plan 2011 is a Native American saying:

Treat the earth well. It was not given to you by your parents, but loaned to you by your children.*

I think the budget guys have a similar philosophy:

Treat the wealth well. It was not given to you by your parents, but loaned to you by your children.

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*The quote may be found at page 2 of the linked pdf file.

Necessity is the Mother of Invention

During the First World War, Imperial Germany was cut off from its sources of fixed nitrogen (mainly Chilean saltpeter and bat guano which it needed to make gunpowder). The ingenious Fritz Haber invented the direct conversion of atmospheric nitrogen to ammonia using hydrogen gas. Haber won the 1918 Nobel Prize in Chemistry for this feat, despite Germany having lost the war and despite Haber's wartime culpability in making things like chlorine and phosgene gases for trench warfare (out of fairness, note that Nobel Laureate Victor Grignard headed up the French contingent of poison-gas warriors). The commercial Haber-Bosch process literally enabled the subsequent worldwide population bloom known as the Green Revolution, though it was reduced to practice by the likes of Norman Borlaug. The Haber-Bosch process is still used today, highly refined, but essentially unchanged. A "Holy Grail" of modern catalytic chemistry is to invent new catalysts that work at normal pressures and temperatures.

During the Second World War, coal-rich Nazi Germany was cut off from commercial sources of crude oil, which it needed to wage highly mechanized warfare. The ingenious Franz Fischer and Hans Tropsch had invented and developed the conversion of coal to liquid hydrocarbons in the 1920's. Their technology was scaled up and used to augment military and domestic liquid fuel supplies. Fischer and Tropsch did not win a Nobel Prize for this feat, perhaps because Fischer died in 1947 (Tropsch had died in 1935). The commercial Fischer-Tropsch process is still practiced worldwide, and could play a greater role for our coal-rich nation, but not under the present Administration, which prefers alternatives.

Among the alternatives is the photochemical conversion of carbon dioxide to a reduced product such as carbon monoxide. link This technology, coupled with existing "syn-gas" technology for converting carbon monoxide and hydrogen (derived from water) to hydrocarbons, is another "Holy Grail."  These research efforts have a way of ramping up as the relative price of crude oil increases and remains high. We may be entering such a phase.

Nobel Intentions

Dr. Chu:  Somehow we have to figure out how to boost the price of gasoline to the levels in Europe.

Mr. Obama: Well I won't raise the federal gasoline tax, that would be a mistake because it would put additional burdens on American families right now.

Dr. Krugman: Look guys, it's easy--ever since we went off the gold standard, we've been on the black gold standard. If we just print more dollars without producing more oil, the price of oil has to rise -as surely as the tides.  Remember, inflation rewards debtors!

Mr. Obama: So I can pay for my programs and cut oil consumption? The average American family won't feel it so long as they keep borrowing.  Win-Win!

Flogging Phlogiston

Oxygen burned two great ideas in chemistry. Not literally, but understanding oxygen and oxidation undid two great ideas. One was called Valence Bond theory and I considered its undoing back here. VB theory is still useful and is taught in middle and high school chemistry curricula. The other great idea was called Phlogiston theory. Of course the Chinese had their own take on oxygen which you can read about here: link

The word "phlogiston" came from the ancient Greek word φλογιστόν ("burning up") and was promulgated by German scientists beginning in the 17th century. The notion had probably been around much longer because the idea was a very intuitive one. Phlogiston theory taught the existence of an element called phlogiston, a substance without color, odor, taste, or mass. Phlogiston was liberated when something burned or slowly rusted. Think of what you feel in front of an open flame. Not really so far-fetched, the notion was close to our modern notion of energy consumption, in so far as we suppose substances like fuels have "energy content." We speak of hydrocarbon's energy content in BTUs as if it were something we could distill and put in a bottle.

Phlogiston was a German notion and was undone by men like Antoine Lavoisier who showed that metals increased their mass when they burn or rust, inconsistent with something being lost or given up. Unfortunately, Lavoisier lost his head in the French Revolution for his royalist sympathies.  A dead cat bounce for Phlogiston occurred around the turn of the 19th century, just after water electrolysis was discovered.


Alessandro Volta's Pile 

When William Nicholson and Anthony Carlisle inserted the two wires from their voltaic pile together into a vessel of water, they also galvanized the entire scientific world, creating a sensation as great as any scientific discovery ever made. In Nicholson's words:

It was with no little surprise that we found the hydrogen extricated at the contact with one wire, while the oxigen [sic] fixed itself in combination with the other wire at a distance of almost two inches.

What actually happened depended on the type of metal wire used: when they used copper, hydrogen gas evolved at one wire while the other wire became "fixed with oxygen" meaning it turned to copper oxide (greenish blue). But with platinum or gold wires, hydrogen gas evolved cleanly at one wire while oxygen gas evolved cleanly at the other electrode. The great puzzle was not that the two different gases were produced, but rather that they were produced at different electrodes. It seemed to everyone that if the gases both came from the decomposition of water they should both appear at the same place.

Now the notion that hydrogen and oxygen were distinct elements was not universally accepted. It was not settled science. One of the doubters was a German named Johann Ritter. Ritter was no slouch.*  He repeated the Nicholson and Carlisle experiments and concluded that it was impossible for the gases to be produced from the decomposition of water since there was no way that a gas could travel through one wire, through the pile, and out through the other wire. The truth, Ritter argued, was that:

Water is an element

In Ritter's view, "oxygen" was just water plus positive electricity and "hydrogen" was just water plus negative electricity. He nearly set science back 2000 years. That water was an element and electricity was like phlogiston was ancient thinking. Great minds, including Michael Faraday, puzzled over water electrolysis for years. Bear in mind that in the early 1800's nobody had yet thought that water could ionize into H⁺ and OH^-. The proton (and the electron) had not yet been discovered. But the Germans ultimately lost the argument.

We now understand that water is consumed at both electrodes and electrons flow into one electrode and out the other:

At one electrode we have:  2H₂O   +   2e^-   ---->    H₂(g)   +    2OH^-
At the other electrode:        2H₂O    -   4e^-   ---->    O₂(g)   +    4H⁺  

I remember this stuff by recalling the origin of the word "oxygen" which means "acid-forming." The electrode which forms oxygen also forms acid. Of course the H⁺ and the OH^- swam the two inches back towards each other in Nicholson's experiment and remade neutral water, and completed the circuit.
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*Ritter was no slouch:

"William Herschel discovered infrared radiation because thermometers, which had recently been developed in Europe, showed a higher temperature just beyond the red end of the visible spectrum of sunlight. The German chemist Johann Wilhelm Ritter (1776-1810), after hearing about Herschel’s discovery from 1800, identified another “invisible” radiation which we now know as ultraviolet (UV) in 1801. He experimented with silver chloride since blue light was known to cause a greater reaction to it than did red light, and he found that the area just beyond the violet end of the visible spectrum showed the most intense reaction of all." reference

Hydrocarbons: Still Our Old Friend

As I write this we're all still watching the horrible oil rig disaster unfold. Here are some spectacular photos of the event via Twitter.

Eleven dead already.  The entire Gulf of Mexico coastline threatened. Is there already talk of this catalyzing a move further away from oil? The fact is that oil and related hydrocarbons are still relatively cheap and plentiful. Or is the whole enterprise just too big to fail?  I worked for a time on a project devoted to making gasoline from natural gas. During this time I became familiar with the business phrase "shutdown economics" which in that case meant that any new technology had to be good enough to make the existing technology unprofitable and pay for the cost of recapitalization.

We'd all like for wind and solar energy to be cheaper. But we're not anywhere close to replacing hydrocarbons.

Can Lithium Help Detroit?

Bolivian Lithium

Back to chemblogging for a bit.  Hmmm, let's see...I left off quite a while ago with lithium, helium, and hydrogen. I'll finish off lithium before moving onto beryllium, the fourth element.

Lithium Pharmacology
Lithium (or more accurately Li⁺) is pharmacologically active and is used to treat bipolar disorder. It's not at all clear to me (nor to Wiki) how this works.  Let's improvise. Here's my armchair analysis:
Observations: (1) In the body, Li⁺ is awash with lots of similar cations, namely, sodium (Na⁺) and potassium (K⁺). Moreover, there's realistically no way that one could swamp the body with so much Li⁺ that it would simply displace Na⁺ and K⁺; moreover, both sodium and potassium are essential and we'd die without them. Better to look for something that Li⁺ does better than Na⁺ and K⁺ do.
(2) Lithium is found in nature as lithium carbonate (in nature, elements tend to be found with other elements for which they have natural affinity). There is also experimental evidence that Li⁺ binds better to carboxylate groups, –CO₂^(-) than do either Na⁺ or K⁺:  ref.  In other words, Li⁺ has a higher affinity for the carboxylate functional group¹ and could displace a greater concentration of Na⁺ and K⁺. The pharmacists already know about this special affinity and Li⁺ is commonly formulated as lithium citrate:

Notice that the citrate has three carboxylate groups. Lithium citrate was once an ingredient in 7-Up, the Uncola, but was removed in 1950. It's important to realize that once in the body, the citrate part is easily chewed up and metabolized, leaving three Li⁺ cations, each in search of a carboxylate. 
(3) Carboxylates are ubiquitous, being the terminal side chain of common amino acids aspartic acid and glutamic acid.
(4) Glutamate is implicated in all kinds of neurochemical functions.

Hypothesis: Li⁺ displaces Na⁺ to such an extent as to affect the role of glutamate. The carboxylate functional groups are intimately involved in how neurotransmissions occur.  Essentially what lithium does is to monkey wrench this somehow. Anyway, it's just food for thought. Prove it wrong. A cursory Google search suggests there is something to this: ref, ref, and ref.

There are other proposed mechanisms of action for lithium and, if interested, check out the Wiki page here.  I love ill-defined chemical mechanisms, especially when an element is involved.  I'll return to this theme when I consider the essential role of boron (element 5, after beryllium) in plants. Meanwhile, I hope a lithium expert finds this blogpost and jumps in to correct me. I will retract the hypothesis.

Lithium Ion Batteries
Lithium ion batteries power lots of everyday electronic gadgets like cellphones, laptops and other electronic gadgets and, hopefully soon, lots of electric cars. Several generations of rechargeable batteries include lead-acid, nickel-cadium, nickel-metal hydride (NMH), lithium, and now lithium ion. By far and away the lithium ion battery is superior--enough to revolutionize the small gadget industry. Why is that?
First, it's very light. Lead-acid (think 12 V car batteries) and NMH batteries (think Prius batteries) are very heavy. Old fashioned carbon-zinc batteries are light but are not rechargable). Weight is very counterproductive deadweight when you're trying to move something around.
Second, lithium has a relatively high redox potential² for conversion of Li⁺ to lithium metal. Early lithium batteries did in fact use lithium metal and lithium ions, however it was quickly realized that the dangers of using lithium metal could not be overcome.  Lithium is a highly electropositive element and would seem well suited for 3 V applications. If you consider that the nominal voltage of common batteries: viz., AA, AAA, C, and D is, 1.5 V you'll realize that a 3.0 V battery would be useful, given that 3 V is commonly acheived by using two 1.5 V batteries in series. (This is why so many devices use two such batteries head to tail).
Lithium’s exceptional light weight is currently wasted in present generation batteries, especially automobile-sized ones: the battery train for the Chevy Volt weighs about 600 lbs. Much of this weight is due to cobalt oxide present. However, next generation breathing batteries intend to do away with the relatively heavy cobalt or iron-based components. I really hope the Volt does well and I suspect it will. Detroit needs a home run like the Toyota Pruis. I think the Volt is especially suited for the urban coastal hipsters. Me? I'll stick with diesel for the time being.

Lithium in Synthetic Organic Chemistry

The wonderful and unique properties of lithium just go on and on. A single inorganic compound, LiAlH₄ or LAH in the parlance, enabled the synthesis of entirely new classes of compounds, including pharmaceuticals. Organolithiums are a class of compounds wherein lithium replaces a hydrogen atom.  They are useful because they allow carbon in a hydrocarbon to behave as a negatively charged anion-a carbanion. Carbon normally engages in chemical reactions as an electrophile, i.e., having a tendency to attract negatively charged coupling partners. An obvious example of this is peptide synthesis in which donor nitrogen meets acceptor carbon.
Alkali metals, Li, Na, potassium, etc. dissolve in liquid ammonia to give intense blue solutions. Liquid ammonia itself is colorless, and so are solutions of Li⁺.  The blue color comes from solvated electrons:
              Na   --------> Na⁺ [e^–]
                        NH₃
The compound is called sodium electride.  You can watch it form here

Worries About Lithium Supplies
Worries about Bolivia becoming the Saudi Arabia of lithium are overblown. First of all, the photos (see above) are deceptive: those miles and miles of white salt flats are not heaps of lithium salt: it’s mainly just dried up sodium chloride. The salts are enriched in lithium carbonates. Unlike fossil fuels, the lithium inside batteries is not destructively consumed. Lithium is not a source of energy: remember that the energy has to put back inside the batteries. We have ample domestic sources for the time being from the brines of Searles Lake, CA and in Nevada.

Last but not least, don't forget the dilithium crystals!
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¹Functional Group defined
² Redox Potential is term of art and usually refers to chemical element's potential to gain or lose an electron. In lithium, there is a high propensity for the metal to lose one electron and thus obtain the noble gas electronic configuration of helium.

Carnot Knowledge: Rudolf Diesel's Awesome Idea

Rudolf Diesel (1858-1913)

Ordinary gasoline engines are powered by the sparked ignition of gasoline vapor compressed with air. The heat of combustion and increased exhaust gas pressure drives pistons, doing useful work derived from the chemical energy stored in the fossil fuel. Gasoline engines behave according to the Otto Cycle and the ideas originally date from the mid-19th century.

Rudolf Diesel, a German engineer, understood the engines of his day and had the radical idea of compressing air inside the piston until it became so hot that fuel would spontaneously ignite when it contacted the hot pressurized air, thus not requiring a spark plug. In essence, Diesel reengineered the existing Otto cycle and invented engines that behaved according to the Diesel Cycle.

Diesel based his ideas on his understanding of the thermodynamics of heat engines, a young science begun by the French engineer Sadi Carnot and who later became known as the father of thermodynamics.

US Patent No. 542,846: "Method of and Apparatus for Converting Heat into Work (Link) was awarded to Diesel and has a clear and concise explanation of how and why diesel motors work. In Diesel's own words (or more likely those of his patent attorney):

The gases in the cylinder are now permitted to expand with gradual introduction of fuel and expansion is so regulated that the decrease in temperature by expansion counterbalances the heat produced by the combustion of the fresh particles of fuel. The effect of combustion will therefore not be increase in temperature or pressure, but increase in actual energy exerted.

Diesel also solved another important problem that still limits the efficiency of gasoline engines, viz., the tendency for gasoline motors to knock or ping due to "predetonation." Autoignition is precisely what diesel motors are supposed to do, albeit in a controlled way.  In a diesel motor, the air and fuel are pressurized separately and then mixed. Because diesel motors burn at hotter temperatures than gasoline engines do, they have a tendency to "burn air," forming nitrogen oxides from the normally inert N₂ and O₂ that make up the air we breathe. Precious metal catalysts are used to convert the nitrogen oxides back into oxygen and nitrogen.

Today, diesel motors find widespread use in nearly all commercial transportation applications: trucks, trains, ships, submarines, and, as I learned from Theo Boehm, even in aviation (BTW, did you know that aviation gasoline still has lead? Link--fine particles of lead oxide (or actually lead chloride or bromide) rain down on us everyday. Europeans use diesel motors far more commonly than we do for personal transportation.

I'm sold on diesels. I own a 2003 VW Golf Diesel (TDI) and I love it. It gets around 43 MPH on the highway and not much less in city because it's a stick. Another advantage to owning a diesel in CA is that they are exempt from smog-testing.

H Is For Humble Hydrogen

The sun consumes about a half billion tons of hydrogen every second, fusing mass into helium and radiating the excess as energy. We just sit back on sunny days and bask in the afterglow of the nuclear holocaust at a very safe distance, thinking nothing of it. Our nonchalance towards any solar dimming is justified by considering that the sun should last another 5 billion years or so.

Hydrogen fuel cells (chemical, not nuclear) are already used in spacecraft, and modern rocket engines burn liquid hydrogen and liquid oxygen. But back on earth, there is talk of using hydrogen as an energy source to replace hydrocarbon fuels. Hydrogen gas burns cleanly, as the very name reminds us: hydrogen = water generating; the catch is that hydrogen gas has to be made because little is found naturally on earth.

By far the cheapest way to make hydrogen gas is from natural gas, CH₄, using a process that co-produces CO₂ (the carbon atom has to go somewhere). But another little appreciated fact is that a big consumer of hydrogen gas is the fertilizer industry—hydrogen is used to make ammonia from nitrogen—and another big user is the food industry—it is used it to hydrogenate vegetable oils. Any large-scale diversion of existing hydrogen to transportation fuels will ultimately raise the price of food via the costs of ammonia fertilizer and food processing costs. Sound familiar?

What’s really needed is a new and different way to cheaply make hydrogen gas—something like the efficient photolysis of water or the electrolysis of water using electricity from nuclear power plants. Both technologies exist, but they are economic nonstarters. For my money, I’d rather see cars run on methane, rather than going through the additional process hoops of converting the methane to hydrogen gas. A similar argument holds for bio-fuels, which I will discuss when I get to carbon and oxygen.

Hydrogen is the most promiscuous chemical element, pair bonding with nearly every element and even forming special bonding threesomes called hydrogen bonds. Hydrogen bonds are the principle force binding the two strands of DNA together. Arguably, hydrogen bonds are present at the conception of human life: when the two single strands of DNA, one from the mother, one from the father, join for the first time, those strands are united by about 3 billion hydrogen bonds. Each one is worth a small amount, but together, summed over the entire double helix, amounts to a formidable binding glue.

The themes of family and weak and strong chemical forces reminds me of some lines from the David Lynch movie “The Straight Story." Richard Farnsworth says (while demonstrating with sticks):

When my kids were young I played a game with them. I'd give each of them a stick. One for each of 'em, and I'd tell them to break it. They'd do that easy. Then I'd tell them to make one bundle of all the sticks and try to break that. And course they couldn't. I used to say that was family, that bundle.