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Sunday, December 11, 2011

How We Know What We Know -- Chapter Two

When I was in my early twenties I was in love.  It was unrequited, but we still got along well and to this day I still say that she is one of the finest persons I have ever met.  I won’t say it wasn’t painful – as an aspie I probably just didn’t have the knowledge and maturity to win her heart (or maybe it just wasn’t “meant to be”, whatever that means) – but I have always been glad that I knew her.  She was a  terrific friend and companion.

One day, we were discussing ancient pyramids, of both the old and new worlds. You might have noticed that among the very large structures built by these ancient cultures (Maya, Mesopotamia, and Egypt mainly) were a variety of pyramids, from step to flat-faced, with the smaller step ones coming first because they are easier to build, and often evolving, as in Egypt about 2500 BC, toward the huge, flat-faced structures (e.g., Giza).  That this came about by improvements in the needed engineering skills is fairly certain (I doubt they needed ancient astronauts, though of course it is possible), and probably also by larger populations, a decreasing portion of which didn’t have to grow food and so were available as necessary labor.  Better political and cultural organization no doubt played a role too.

In chatting on the subject, she made a claim which I immediately found hard to swallow.  I can accept the Egyptians and Mesopotamians influencing each other; the areas are nearby in the Middle East, while excursions (and even conquests) between the two are common in history.  It’s quite reasonable to imagine (though I am not certain) the two cultures shared and contributed to each others’ pyramid construction techniques and strategies.  I am ignorant of whether this really happened, but it is plausible and easy to believe.

But Egypt/Mesopotamia influencing the Maya?  She was quite sure of this; but it was only because she couldn’t imagine two separate cultures building such common structures, especially such massive ones, without their being a physical connection.  To be fair, the idea sounds superficially reasonable and even compelling, this idea of Egyptian boats making the trans-Atlantic voyage to the Yucatan peninsula and instructing the Mayans on the time-honored art of pyramid building.

What a minute, though.  Ancient Egyptian boats making trans-Atlantic voyages?  In fact, this is a real problem.  As the Europeans were to find out in the 15’th and 16’th centuries AD (and the Chinese about the same time), there are huge differences between large ocean-traversing vehicles and those who stick to rivers, bays, and small seas and lakes.  You need deep, complex keels in the ocean variety to handle the higher and more violent waters and storms, deep harbor ports to handle such vehicles, which are larger, sturdier boats (made with hard wood at least, which Egypt had little of) with more men and much more supplies (to handle journeys of months instead of days or weeks at most), and so on.  Now, I have never heard of any discoveries of these things being made in Egypt through the many centuries she was a great power in the western world; and we certainly would have found them if they’d existed, for there is no lack of archeological exploration there.  What we do know is that Egyptian boats were mostly made from papyrus and other reeds, hardly up to ocean travelling needs.  Indeed, these ancient, (mostly Mediterranean and Black) sea travelling boats stuck close to shorelines for safety, something you couldn’t do in a large ocean.

This would seem to make it virtually impossible for any ancient Egyptians/Mesopotamians to reach the Yucatan Peninsula in Central America.  Even if one did, by accident say (this is possible, with incredible luck), why would they carry pyramid builders and technology with them?  They would have had no ideas what to expect, besides, perhaps, an end of the world to fall off (the ancient Egyptians didn’t know Earth was spherical, a fact that was discovered by the Greeks many centuries later).

I think all this alone destroys this hypothesis, though it is not always easy to make such statements with certainty.  For there is still the fact of similar pyramids in old and new world cultures, something that still needs explaining.  To be complete, the one fact that fits poorest for my friend’s idea (perhaps even worse than the ship dilemma) is that the new world pyramids were built many centuries and even millennia after the old world ones.  If an Egyptian boat were to somehow cross the Atlantic at its pyramid building times it would not have encountered a culture that could imitate much of the Egyptian/Mesopotamian technology/political/cultural levels even to save its life.  Yet by the time the Mayans (and some other Central American cultures) were ready for it, the old world was far beyond pyramids, having acquired the ability to build more complex and useful structures (oh, say, like the Valley of the Kings, the Greek Parthenon and Roman aqueducts, maybe even medieval castles).

*          *          *

Think about it.  You are a well organized, powerful, and highly command-centered Neolithic stone-age culture, with a good supply of available manual labor (including, no doubt and, alas, slaves) and rock.  Time, as in decades, you have in abundance too, or so you hope.  As the leader of this culture you want to construct huge monuments to your greatness, both to intimidate the masses and your neighbors, and to make you remembered for “all of time.”  What would you construct?

Your engineering skills are still pretty primitive for such tasks, so you need the easiest to build, strongest, and most sturdiest structure you can manage.  Is it hard to see that this would be a pyramid, starting off with small, steps ones and building them larger, with smaller steps, as your engineering and architectural skills were acquired over decades and centuries?  A pyramid is in fact very strong, with a stable, a broad, flat bottom combined with tapering construction above it.  I’m sure it requires the least engineering and architectural mastery, as you are just basically carving out (shaped) stones from a quarry, dragging them to the pyramid, and using scaffolding or levering to get them on top of the existing stones.  You may or may not have wheels (as in logs?) and animal power to help you, but that just increases the time it takes.  Enough people, time, and sophisticated enough stone carving tools, and it can be done in a lifetime or less, maybe a decade or less.

Apparently, my friend didn’t think of all these objections to her “hypothesis” (better just called a belief).  She’d stumbled across one fact, the similarities between old and new world pyramids, and that was good enough for her;  there was little or no further researching, or thinking, or skepticism.  I have an unpleasant feeling that that is the way many if not most people think, especially B people (As can’t do this).  They find one or two facts (or factoids even) which suggest an exciting idea, or one that fits a pre-existing idea, and if they look or think further it is only to confirm the idea, which becomes a simple article of faith from thereon.

I have used the word hypothesis occasionally here, as though it is interchangeable with belief or idea, or even speculation, but to the scientific mind the words hardly approach each other in their meanings.  I haven’t used the word theory yet, which I will now, for again in many minds sets up an equivalency:

Belief/Idea/Speculation = Hypothesis = Theory = Truth

It’s clear to me that my friend, though quite intelligent, thought largely along these lines, while it’s a pretty standard philosophical approach for most of Earth’s population.  Unfortunately, it is wrong, dead wrong,  a mistake no scientists worth rock salt would ever make.  I also think it is why B-type people are much more prevalent than they ought to be.  I also connect it with the authoritarian thinking, mentioned in the last chapter, which can bury human curiosity under a think, wet, cold, woolen blanket; for it is seriously, and even dangerously, fallacy supporting.  My friend was intelligent, but she didn’t know how to think or question things.  Shame, though I still respect her.

*          *          *

Belief/Idea/Speculation (BIS) = Hypothesis = Theory = Truth.

Is this truly the way type Bs (not all, to be fair) think?  Type As, definitely not:  they could not perform their jobs, or carry on with their enthusiams, if they did.  But is it as common as I have implied?  And if it is, what is really wrong with it?  We are pretty much all after the truth, after all, and this could be a formula for it, one I simply don’t appreciate for prejudices of my own.

Actually I don’t think it is all that too common as pessimism would suggest, at least not in so pure a form.  But people do routinely make confusions here.  This is important:  a big part of science is giving words and concepts precise, accurate meanings, ones that can then be used in almost mathematical formulations.  And so, if we are to use the words/concepts here in like fashion, we must do the same.  Then, perhaps, we can answer the question I raised at the beginning of the section.

BIS’s are what most of our minds are filled with most of the time, even, I strongly expect, most scientists.  E.g., we Believe in an Idea called God, or maybe various gods; or if we don’t, we still Speculate about whether our sentience is a soul, and whether it survives death, by becoming, say, part of some BIS called “cosmic consciousness”.  Or, to be less esoteric, we have plenty of BIS’s about the people in our lives, about politics, economics, religion, and the many, many other things we “think about without thinking about.”

I am not criticizing here.  The human mind probably has to work this way, if for no other reason that if we were as meticulous about science as we are about everything else, it would be difficult to get anything done!  Remember, too, our brains have been largely wired by genes we’ve inherit from our stone age, uncivilized ancestors.  Making “snap decisions” or acting on gut feeling, without too much asking and exploring, was, for most of our evolution, the better way to save your life and pass on your genes.  But  the result is, we’re stuck with them, at least for the time being.

I think my friend’s idea about Egypt helping with new world pyramid building is a textbook example of a BIS.  It is so easy to bring this Idea down, by being skeptical and thinking about it, that she must have never done those things.  No doubt she just liked the idea so much, and, having one fact to support it, simply assumed that meant it was true.  Man BIS’s are based on the one fact fallacy.

*          *          *

Let’s focus our microscopes on the other three words of the equation:  Hypothesis, Theory, and Fact.

First thing that needs to be said is that, despite all the = signs, from a scientific view they are not equals at all, but distinctly different entities.  At the same time I’ll add up front that in fact they are also not really so distinctly different, but overlap to considerable degrees. 

Let’s start with the word hypothesis, and as usual, an example of it.  I think my counter-arguments to my friend’s idea constitute a valid hypothesis.  It is not theory, and certainly not fact, but simple hypothesis.  First of all, after all I not only attacked the idea (with gusto, of course; all ideas should be attacked with gusto), but presented counter-ideas of my own; for example why pyramid building is natural for a well organized, stone age culture at an early age, and why.

But I did not present any supporting evidence for that, other than the “it should be obvious and here’s why” implication.  Given that, you might dispute my claim to hypothesis status!  But I did give, I believe, some pretty sound logic for it; more important than that, logic that can be explored and tested to see whether it holds up to test.

“Whether it holds up to test” is a great deal of what true hypotheses, the ones in type A minds, concern themselves with.  For an hypothesis is a concept that proposes something, or explains some phenomenon, and which fits all known facts, contradicts none, and can be further tested (that is, can it make predictions).  I believe my friend’s pseudo-hypothesis has actually failed this concept (in her defense, though, she isn’t here to counter her critic, which really isn’t fair), while mine passes muster – probably; I am not an expert in the subjects and there could be facts difficult to fit into it – if only by the skin of its teeth.  And, to reemphasize, it is nowhere near to being a theory, or a fact itself.

I am taking a conservative approach here, as should all scientists.  At heart, we’re curmudgeons who hale from Missouri and often don’t believe things even when we see them with our own eyes (not a good reason to believe just about anything, by the way).  Propose something to a scientist and the best you’re likely to get is, “That’s interesting” along with appropriate body language, or something like that.  Believe it or not, it’s a compliment.

Such are the basics behind hypotheses.  So, next time some fascinating sounding thought comes to you, wait until you’ve checked it against all the facts and logic you can find, and think of some ways it could be further tested, before you announce it to the world.  Not that the thought is automatically useless if you don’t; but then, you’ve just been lucky.  My friend was not lucky.

*          *          *

Theory and fact are more difficult to pin down, because they really have multiple, sometimes interlocking, meanings.  In common parlance, and often in science too, theory just means an explanation for something, even if not a necessarily proven true one (though it must have good evidence for it); in the former, common parlance, case, but decidedly not for scientists, it is not even a necessarily clear, well-supported explanation.  So if, for example, I propose an explanation for how stars form (already been done!), and it passes the hypothesis examinations, people will call it a theory.  But they might not call it a fact because it still hasn’t passed enough testing.

Charles Darwin’s idea of evolution by natural selection was initially an idea, then a hypothesis, and is now, as it is usually called, a theory.  It’s an explanation, true; but it is also, because it has passed so many tests and has so much evidence on its side, a fully-fledged fact as well.  Einstein’s theories of special and general relativity also get similar, justified, status.  As does the atomic theory of matter.  They’re explanations and they are facts.  Nobody seriously disputes this.

At the same time, as a theory is in another sense also just an hypothesis that has stood up to further testing and observation, such that it can be a claim to fact that may or may not (though most facts do) explain other facts, or support other theories.  I’ll put Alfred Wegener’s theory of continental drift in this arena.  The theory says that the different continents move around on the ocean beds, occasionally joining each other and then breaking up, as shown below:

Figure II.

     In fact, for much of its existence this theory wasn’t even taken seriously even as an hypothesis by most of the scientific community.  This was partly Wegener’s fault, for he proposed causes for continental drift that were clearly absurd – I emphasize however that this really should not be regarded as evidence against an hypothesis – and mostly (I believe) that community’s fault for not supporting an out of league player (Wegener was a meteorologist by training, not a geologist).
Currently, the theory now is not only clearly true, but is a theory in both senses:  continental drift is a fact (with clear, proven causes), and it is a theory that explains many other phenomena about Earth, ones that had puzzled scientists for a long time.  We now call it rightfully  the theory of plate tectonics, after the true causes of drift.

*          *          *

Fact.  Now, don’t go thinking that fact means “naked observation by the senses” or anything like that.  I already alluded to this, but this is a good time to go further.  If observation really is equal to fact, then the (fact? – maybe you’re lying, or psychotic) that you just saw someone walk through a wall of solid concrete without smashing it apart in someway a fact, or merely an observation – that is to say, a visual illusion?  I’m sure you’ll conclude the latter, even if you have no idea how the illusion was pulled off or how convincing it is.

This may put us in a pickle.  Facts aren’t observations, but don’t they have to be, somehow, supported by observations?  But how do we know whether we’re being fooled or not by these other observations?

One of the problems of science is that it really can’t make indisputable proclamations about the universe.  This makes science vulnerable to “straw men” arguments, often easy to demolish, but unfortunately inevitable if we want to keep it pure.  Yet we can still make real progress here.  For example, sticking with our concrete-traversing man scenario, what would happen if we were to view it from all viewpoints, even those slowed or speeded up in time?  Why, somewhere the illusion would certainly be revealed, for a lot of magic is based on the magician having his/her audience in a chosen viewpoint.  The brain  insists on interpreting sensory input in certain ways, another evolutionary trap which actually is reasonable but sometimes leads us to error.

This suggests a good way of determining fact (if not with infinite certainty).  We make our observations from as many viewpoints as we can, and compare the results.  If they agree, especially repeatedly, we accept them as true; otherwise, they are spurious observations, fascinating possibly but of little scientific value.  Of course, this is not always easy to do!  Do two astronomers, gazing at the same phenomenon a billion light-years in space, really constitute two viewpoints?  In some ways yes, in others certainly not.  But it is the best we can do in this case.

*          *          *

One conclusion of this chapter is that the dividing line between hypothesis, theory, and fact is not always clear, in fact it can be quite broad and grey, the subject of innumerable, passionate, debates.  But, I maintain, the line between the first part of the equation, the BIS, and the others is night and day.  And, I emphasize further, this is the line that is so precise in type A’s minds, but can get so muddled in type B’s.  I think this is the main cause of why B’s (say they) don’t get science and math, beyond any natural talents in either areas.

So remember:  you can have all the ideas you want, but if you want them widely accepted as true, you must eschew the BIS approach and embrace the scientific one.  And good luck to you, for it can be and often is a hard trek.

Saturday, December 10, 2011

Kepler-22B; A Warning or Two

The recent discovery of planet Kepler-22B (orbiting the sunlike star Kepler-22) has set off a flurry of articles and other printed/spoken material speculating that we have at last found another Earth-like planet in our immediate stellar neighborhood (the star Kepler-22 is about 600 light-years from our sun, making it quite close insofar as intra-galactic distances are concerned; the Milky way is approximately 100,000 light-years across).

In science however, excitement must be tempered by sober examination of evidence, and there are some good reasons why we should not get too excited by Kepler-22B just yet.   In the first place, we don’t have a good estimate of its mass yet, and probably won’t for a few more months.  This is the most critical consideration as to whether the new planet is a (relatively small) gas-giant world, like Neptune or Uranus, only about half their diameters, or is truly an Earth-like planet, one with a rocky core probably covered with deep oceans.

If the first scenario is true is found to be the truth, this doesn’t automatically rule out life on the new world.  It might still possess liquid water, here as cloud layers, and life could possibly begin in droplets or drops of water seeded with ammonia, methane, hydrogen cyanide, and carbon dioxide, a lá the Stanley Milgrim experiments of the 1950s.  A distinct planetary surface is not actually needed for life, or so current thinking runs.  However, its seems doubtful that such life would have evolved far beyond the single cell, or prokaryotic, stage.  Definitely worth knowing however, if it turns out true.

The other, mass-determined, probability is that of a “super Earth”, a planet like our own, only considerably larger, and one probably covered by ocean-girdling waters and a thick, greenhouse atmosphere.  Again, primitive life is a good candidate for the place, and here even complex, multi-cellular organisms may have gotten a toe-hold.  They could be swimmers and flyers, though almost certainly little in the way of land dwellers, for there would be little of any land to dwell on.  Still, polar icecaps might provide some of this.  A lot depends on the depth of the greenhouse effect, driven largely by water vapor, carbon dioxide, and methane.  All three gasses should be copiously produced by volcanism, so we shall see. Volcanism in turn is driven by a hot liquid core containing sufficient amounts of radioactive atoms, atoms like uranium-235/-238, thorium-232, potassium-40 and strontium-87.  Earth has significant amounts of them (creating also our strong magnetic field which protects us from the solar wind) because the creation of our solar system was probably initiated by a supernova type-II explosion, seeding us with heavier elements, but it is not clear whether Kepler-22 was born under similar circumstances (it is not all that unlikely however, so we can reasonably speculate it).  If not however, Kepler-22B might be frozen over, with little internal heat or heavy elements, leading to few prospects for life.

All this is speculation right now, but it may be of the purely academic kind, for other conditions are needed for life.  The biggest problem is the apparent lack of large gas giant worlds, situated further out than Kepler-22B.  They may still exist, in slightly different orbital places than 22B, such that we don’t see their occultations from Earth; doppler “wobbles” in the star’s spectrum might yet root them out.

If they are not found, however, this is troubling for life’s prospects on 22B.  Jupiter and Saturn stand as staunch shields against a large number of asteroid and comet impacts to our planet, impacts that nevertheless occur to a disturbing degree and which could wipe out all life here if large enough ones occurred with sufficient frequency.  But we have a couple of heavy duty bar bouncers that either suck up those impacts themselves, or hurl the offending rock/ice worldlets out of the solar system, or park them in the asteroid belt.

If Kepler-22B doesn’t have its own bouncers, then it is probably being regularly pounded by asteroids and comets, so much so that life can’t get started there.  Now perhaps its not that bad a problem out there because the Kepler-22 system was not the result of a supernova explosion; but then there might not be enough heavy elements to make a hot, molten core, with its attending strong magnetic field and copious atmospheric components.

Then there’s the other problem, which I’m not certain is truly severe or not.  Earth has an axial tilt of 23° , which is almost perfect for our seasons and the life adapted to it.  The tilt does not vary greatly, and supposedly we have our large moon to largely thank for that.  The reasonable length of our day is also due largely to the moon.  Frankly, I don’t know how large of a problem this really is; with the exception of Uranus (with a 98° axial tilt, rotating virtually on its side), all the planets rotate on roughly vertical axes to the solar system’s orbital plane, and only Mercury and Venus have unusual days, in the first case one locked in a 2:3 resonance with its solar orbit, and in the second, Venus’, case a slow retrograde axial orbit (opposite to its movement about the sun).

If these parameters are important (as suggested by the “Rare Earth” hypothesis) then 22B could be in big trouble, though this is not certain.  But all of these considerations, taken together, should keep our enthusiasm in check as we explore Kepler-22B further.

Wednesday, December 7, 2011

Another Mixing Snafu

I just got nailed on another reaction of household products, this time regular bleach with toilet bleach.  Remember that regular bleach is just sodium hypochlorite dissolved in water:

NaOCl (H2O) ® Na+ + OCl-
OCl- + H2O ↔ HOCl + OH-

H+ + Cl- + OCl- ® OH- + Cl2
H+ + Cl- + HOCl ® H2O + Cl2

In both of the bottom reactions gaseous chlorine is generated in serious quantities.  This is because often, not always but in this case, which I would have known had I bothered to read the labels instead of just assuming, toilet bleach is fairly concentrated hydrochloric acid.  Needless to say it starting foaming at once, and when I came had just enough to flush before being driven out, coughing and tearing.

Lesson:  read labels on chemicals before using!

Making Hydrochloric Acid from Household Ingredients


Making Hydrochloric Acid from Household Ingredients

I used to do this when I was young.  I’m uncertain now:  could it not be considered a terroristic threat?  The times, they are a changing!  Anyway, into the science.

Hydrochloric (HCl) acid is simply a solution of the gas HCl (hydrogen chloride) in water.  The basic acid-forming reaction is:

HCl + H2O ® Cl- + H3O+

H3O+ ↔ H+ + H2O
The main acidic species can be considered either H3O+  or H+ , although the latter is usually used as it is clearer and more consistent.  In almost (but not all) all water based acids, this is the actual acidic species, whatever the starting acid (nitric, sulfuric, acetic, etc.) is.

There are a number of industrial and lab process to make HCl acid, usually from other strong mineral acids.  Another way, however, is to generate HCl gas directly and dissolve it in water (it is highly soluble, almost as much as ammonia).  The household method uses this approach.  Questions:  how do you make HCl gas, and how to you get it into the water?

Warning, Warning!  HCl gas is very irritating and corrosive, so you have to set up some kind of protection for your lungs and throat and eyes before generating it!

At a young age, I loved to tinker with chemicals (perhaps not a good idea when I look back on it, but I was usually reasonably careful), both those I found in the house and those I got in chemistry sets.  And I loved to read chemistry books and ponder what might happen if you mixed such and such with so and so and heated them or dissolved them in water.  Amazingly, I still have all my body parts and they all work well, which might be something of a wonder.

In this case I noticed something.  It seemed as though if you mixed ordinary table salt and baking soda and heated them strongly, you might get the following reaction:

NaCl + NaHCO3 ® HCl­ + Na2CO3

In which the two reactants swapped the hydrogen and chlorine,  Further, since HCl was a gas, it would escape the reaction mixture (the upward arrow) and constantly drive the reaction to the right.

Of course I had to try it.  Now, if I’d had a balance, I’d weigh out 5.85 grams of salt and 8.8 grams of baking soda.  This is one tength of a mole of each product, thus an equal number of molecules of each, perfect for the 1:1 reaction.  It would have yielded 3.85 grams of gaseous HCl ( and 9.4 grams of Na2CO3) .  The two weight combinations on either side of the arrow equal, as they should.  I did not have a balance however, and so used a teaspoon or tablespoon of both reactions – good enough.

Now here comes the part where you shouldn’t have done what I did.  I would mix both reactants in an Kimex glass laboratory grade Ehrlenmeyer flask (the triangular shaped one), place the flask on one of our electric stoves, and (at least have the sense to) gradually heat the flask until the stove temperature was at or near high.  I know that gaseous HCl was irritating and corrosive, so I would carefully smell for any gasses coming through the top of the flask.  Sure enough, I found myself tearing and coughing pretty soon, and I knew my hypothesis was a triumph.  The question now was, how to deliver the gas into (preferably cold) water?

You’ve already noticed that household ingredients aren’t quite enough, you also need some laboratory equipment, mostly glassware.  I had such from my chemistry sets:  Ehrlenmeyer flasks, beakers, corks/rubber stoppers that fitted the flask and had a hole large enough for the glass tubing, the tubing, and an alcohol burner I could use to bend the tubing from the top of the Ehrlenmeyer over to the beaker (more than a ninety degree angle) – not as easy as it might sound for glass work requires some practice and experience.  (You can no doubt still get these things, though I don’t know if you’ll attract unwanted attention doing so).

Let’s assume you have a desktop balance for weighing chemicals, though don’t ask me how much they cost; anyway, you don’t need a highly priced one.  Now, if you weigh amount of reactants in the flask as described above, you should generate 0.1 mole (8.8 grams) of HCl gas when you heat it strongly.  After pouring the reactants into the flask, next, assemble the apparatus. The stopper should fit tightly inside the Ehrlenmeyer, the bent glass tube pass through the stopper (not too far, though, just enough to pick up any gasses and deliver them!), and the other end of the tube should reach the bottom of the beaker, which should hold about 100 milliliters (~ 1/10 of a quart, or half a pint or so – use a graduated cylinder if you can) of cold water.  Now strongly heat the mixture in the flask.  What you’ll observe is curious.  First, a stream of bubbles will emerge from the beaker end of the tube, rising and escaping into the air.  Don’t be alarmed; this is just the heated air being forced from the flask through the tube.  What happens next is the main show.  The bubbles stop, and the gas level in the beaker stays pretty much flush with the water.  What is happening here is that HCl gas is now being generated rapidly and, being highly soluble in water, immediately dissolves when it hits it, leaving no more bubbles.  Your HCl acid is starting to form!

You should keep this reaction/process going until you observe the following.  As the reactants are consumed, the HCl is produced in smaller and smaller quantities; and, again because it is so soluble in water, begins to suck liquid up the tube from the beaker.  At this point you should stop the reaction (turn off the heat and move the flask off the stove, remove the flask + stopper + tube from the beaker, etc.).  You DO NOT want water pouring back through the tube into the Ehrlenmeyer under strong heat – I never tried this, but I assume the water will flash into steam, at least cracking if not exploding the Ehrlenmeyer, thereby releasing a lot of acid and HCl gas into the atmosphere, any probably other nasties I haven’t thought about.  All in all, don’t let this happen!

Let it all cool down for a while, before disassembling everything and thoroughly washing out everything but the beaker and its contents (use lots of water, on your hands too).  Now, if the reaction has gone to completion (though remember, some HCl is lost), I figure the concentration to be 0.1 mole HCl gas dissolving into 0.1 liter water, giving around a 1.0 molar (M) solution.  This is a fairly potent concentration (if you get it on yourself, wash thoroughly with water).  It’s more than enough to dissolve aluminum and tin foil, magnesiumzinc, probably lead and iron and some other metals, giving off streams of bubbles of hydrogen gas as it does so (this is also potentially hazardous, and hydrogen gas is highly flammable).  Remember mixing vinegar (a dilute solution of  acetic acid, CH3CH2COOH) with baking soda and watching it fizz up?

CH3CH2COOH + NaHCO3 ® Na+ + CH3CH2COO- + H2O + CO2

The CO2, or carbon dioxide, is the gas that fizzes up, just as from a can of beer or soda.  If you substitute the weak and highly diluted acid vinegar with fairly concentrated hydrochloric acid, the reaction ought to be considerably stronger:

HCl + NaHCO3 ® Na+ + Cl- + H2O + CO2

Not that I remember trying this.  Oh, one more thing; I’m pretty sure that you can make the acid highly concentrated (though I don’t recommend this, however, as it is VERY HAZARDOUS at very high concentrations), simply by upping the amount of reactants.  Multiply the reactants by five or ten (you may have to run the reaction several times, or find a large enough Ehrlenmeyer flask), and you should get five-ten molar acid.  Again, something you really shouldn’t play around with, unless you know how to do so safely).

On Curiosity (From WONDERING ABOUT)


The humility I have described here is not the humility we see (not always in sincere form) in various Eastern religious leaders and the like, although it is related.  I am speaking of intellectual humility:  the ability to accept that anything one has come to believe, whether it be from schooling or a church, from books, parents or other authorities, or even as the product of one’s own observations and thoughts, could genuinely be mistaken; mistaken no matter how much observation and thought or the weight of authority or time lend to it.  Or how many people hold the belief, for how many centuries.  It is the recognition of human limitations and fallibility, even among the most brilliant, well-educated minds.  My personal favorite example of this is Einstein adding the so-called Cosmological Constant to his equations for General Relativity to prevent, for what were mainly esthetic reasons of his, an expanding (or contracting) universe, something which his raw equations implied.  When Edwin Hubble was within barely a decade to demonstrate by his observations of the red shifts of distant galaxies that the universe is in fact expanding, Einstein pronounced this ad-hoc addition of the Cosmological Constant the greatest blunder of his career.  What makes this example my favorite is how a more recent discovery in cosmology, that the universe is not only expanding but that, contrary to all expectations the expansion rate is accelerating (the mutual gravitational pull of the galaxies ought to be slowing it down, yet it is speeding up), has resurrected Einstein’s self-disavowed constant, albeit in somewhat different form.  Einstein’s confession of his greatest blunder may thus prove itself an even greater error, an irony I have to expect he would have enjoyed.

Another, important aspect to humility is the overwhelming feeling, shared by most of us I suspect, at looking upon a universe not only greater than our ability to fully understand, but, as the biologist J.B.S. Haldane observed (though he used the word queerer rather than greater), greater than we can understand.  One of the most wondrous and compelling things about science, which is such a large part of the reasons I have spent a lifetime immersed in it, is how strange and wonderful it can make the most “ordinary” of things, simply by the act of explaining them.

Walt Whitman, "Leaves of Grass"

WHEN I heard the learn'd astronomer,
When the proofs, the figures, were ranged in columns before me,
When I was shown the charts and diagrams, to add, divide, and measure them,
When I sitting heard the astronomer where he lectured with much applause in the lecture-room,
How soon unaccountable I became tired and sick,
Till rising and gliding out I wander'd off by myself,
In the mystical moist night-air, and from time to time,
Look'd up in perfect silence at the stars.

Tuesday, December 6, 2011

Reaction of Bleach with Detergent?

      Here’s some more interesting household chemistry, one that I just discovered.  I wrote about the dangers of mixing bleach and ammmonia before, but naïvely thought that bleach and pure detergent (like dishwashing liquid) was perfectly safe.  In fact, it’s not particularly hazardous, but there is some chemistry going on and some precautions one should take.

It’s obvious that chemistry is transpiring because when the mixture is made, there is some some significant foaming and a mild temperature rise that results.  Again, neither is dramatic, and both cease soon, giving you a stable liquid (which is great to use on sinks, pots and pans, and on other kitchen or bathroom surfaces).

Of course, I’ve been trying to squirrel out why all this happens.  What follows doesn’t come from any probing research but are just my own ideas and chemical knowledge.  The first thing that strikes me as that when you mix bleach and detergent, you’re setting up reaction between  bleach, which is a solution of sodium hypochlorite, and detergent (usually), a sulfonic acid:

NaOCl + H2O ® Na+ + OCl- + ( H2O) ;

OCl- + H2O ® HOCl + H+ + Cl-;

R-(S(=O)2)-OH  + OCl- and/ or HOCl ®  ?;

     There are other possible reactions going on too; this is not as straightforward as I thought it was going to be!  There’s another clue to what’s going on, which is that I found the evolved gas odorless and colorless.  Now if it had been something like chlorine or sulfur dioxide, there was enough that I should have picked up the pungency or even color of these two compounds.  That leaves us with hydrogen and oxygen, which are both colorless and odorless.  Now, I’making oxygen the more likely of the two because I espy a straightforward way of evolving it (and one consistent with all observations of the reaction), while a I can’t see too many ways it could be hydrogen.

Take the S(=O)2)-OH part of the sulfonic acid.  I can easily imagine it reacting with HOCl:

S(=O)2)-OH + HOCl ↔ S(=O)2)-Cl + HOOH

The reaction yields the chlorinated version of the sulfonic acid (detergent), the properties of which should not be too strongly altered; and hydrogen peroxide, which in the vigor of an exothermic chemical reaction can break down into water and ogygen, foaming it up and realeasing heat.  That’s right, I’m suggesting the gas is oxygen (this is easy to test, by the way; just stick a smoldering match stick end into it and see if it flares up brightly).

Also, note the ↔ symbol I use for the reaction direction, instead of the single headed arrow.  I’m suggesting that this is a reversible reaction; it can go either way, as long as some other process doesn't contiuously consume one or more of the reactants/products.  Many chemical reactions proceed this way.  In the reaction above, as long as the HOOH is breaking down into H2O and O2 then it must keep proeceeding to the right, because both the oxygen escapes the mixture.  Two things to bear in mind here, however; first, the reaction is obviously not very strong (or it would get hot and foam up dramatically, perhaps even explode; concentrated HOOH is most unpleasant stuff), and second, the moment the bottle of bleach + detergent is closed tightly the back pressue of oxygen building up in the bottle essentially brings the breakdown of HOOH to at least a near dead stop, and then the entire reaction can go merrily back in forth in equibrium mode.  That’s why it quickly cools and stops foaming.

So what I am proposing that you end up with an equibrium mixture of bleach, detergent,  chloronated detergent, and HOOH (hydrogen peroxide).  If so, that makes it an especially effecting cleaning/bleaching mixture, as all three components will contribute their share.

At least, this is the best I can make of it on short notice.  I’d be fascinated by alternative hypothesis.

Representation of a Lie group

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Representation_of_a_Lie_group...