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Why is chemistry unpredictable?

First of all, I'd ask: what do you admit as "chemistry"? You mentioned thermodynamics as being a field where you have "models to predict results". But thermodynamics is extremely ...
orthocresol's user avatar
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44 votes

Why is chemistry unpredictable?

Let me contribute two more reasons which make chemistry hard to analyse from a purely theoretical standpoint. The first one is that, viewed very abstractly, chemistry essentially relies on the study ...
Nicolau Saker Neto's user avatar
40 votes

Why is chemistry unpredictable?

Parts of chemistry have predictability but the combinatorial complexity of what is possible leaves a large amount of space for things that don't follow the rules Some of the ways chemistry differ from ...
matt_black's user avatar
23 votes

Why is chemistry unpredictable?

Predictabilty is essentially determined by the level of detail you need to accurately model the phenomenon you're trying to predict. Models that require little detail to capture the phenomenon of ...
theorist's user avatar
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22 votes
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What happens to the argon in the Haber-Bosch process?

Inert gaseous components such as methane and argon are indeed should be eliminated from the system in order not to lower the partial pressure of the reactants too much. Technically there is usually a ...
andselisk's user avatar
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21 votes

Why is chemistry unpredictable?

"it seems that every other STEM field has models to predict results (physics, thermodynamics, fluid mechanics, probability, etc) but chemistry is the outlier" This is only partially true, ...
Zhe's user avatar
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17 votes

Why is chemistry unpredictable?

There are some great answers to this question already, but I'd like to provide a more practical boots-on-the-ground answer from my own perspective as an organic chemistry PhD who did computational ...
Ingolifs's user avatar
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13 votes

Is there a simple way to distinguish grades of purity for copper metal?

It is unlikely that there is a simple method, not involving relatively expensive chemical analysis, for distinguishing 4N, 5N, and 6N copper specimens. Shown below is a photograph of some copper ...
Ed V's user avatar
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12 votes

Why is chemistry unpredictable?

To me, it seems that every other STEM field has models to predict results (physics, thermodynamics, fluid mechanics, probability, etc) but chemistry is the outlier. What about structural engineering? ...
Phil Frost's user avatar
7 votes
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Why are the rare Earth elements divided into light and heavy categories?

Though scandium and yttrium have lower atomic mass, they fall in the category of HREEs. The classification seems to have something to do with the formation of REE ores. Here is an extract of Wikipedia ...
Lynn Gu's user avatar
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6 votes

Why is chemistry unpredictable?

Any basic text in Organic Chem has a table of contents.So for a given transformation such as reduction it will list reagents( the chemicals or conditions,eg heat ,light,that appear above the arrow ...
Bob Moriarty's user avatar
5 votes
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What is the difference between an industrial and a laboratory production method?

This answer will be separate in few parts. In the first one I will just make a review of the scope between lab an industrial scale. In the other parts, you’ll find some things more deeply explained ...
ParaH2's user avatar
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5 votes
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Percentage yield of Haber process

Chemical reactions may be performed in sequences (equally known as batches), or continuously. The two differ e.g., by residence time of the reagents and products in this container. The former form is ...
Buttonwood's user avatar
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4 votes

What happens to the argon in the Haber-Bosch process?

Andselisk's answer focuses on the way the ammonia plant can be used to "produce" argon byproduct for sale, but this is by no means essential. The ammonia reaction cycle is continually purged ...
Level River St's user avatar
4 votes

Separation of sulfur dioxide and sulfur trioxide in the contact process

You are true that $\ce{SO2}$ is very soluble in water but it depends on the temperature. Also, $\ce{SO3}$ reacts with water then dissolves in it in a very exothermic way. My understanding is that, if ...
SteffX's user avatar
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4 votes
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Working with typical glass: What temperatures would I be dealing with?

The softening point of glass depends on its composition. For example, 1650°C for fused silica (pure $\ce{SiO2}$) 821°C for Corning Pyrex 7740 borosilicate glass 713°C for Wheaton 900 soda-lime glass ...
DrMoishe Pippik's user avatar
4 votes

Percentage yield of Haber process

It is the question of equilibrium versus nonequilibrium yield and production rate. Maximizing the ammonia output flow is not the same as maximizing the reaction yield. Approaching the equilibrium ...
Poutnik's user avatar
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4 votes
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Is Silica Gel fit for Ultra-High Dessication?

Silica gel is really one of the best desiccants known. But it has to be thoroughly dehydrated at high temperature. Usually silica gel contains a small amount of cobalt chloride $\ce{CoCl2}$ : blue ...
Maurice's user avatar
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4 votes
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Do dessicants work inside of a freezer?

Yes, an effective desiccant would help lower the amount of water vapor in a container and speed freeze drying in a sealed system. That said, freeze-drying usually employs continuous vacuum, because ...
DrMoishe Pippik's user avatar
3 votes

Is there a simple way to distinguish grades of purity for copper metal?

I don’t think there is a good chemical option to solve your problem, unless you do tests for particular contaminants, which is too much work. A relatively simple option is magnetic sputtering, or ...
Surprised Seagull's user avatar
3 votes
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Monosodium Diphosphate (NaH3P2O7) Preparation

$\ce{NaH3P2O7}$ is an intermediate acid-salt formed during the neutralization of pyrophosphoric acid ($\ce{H4P2O7}$) which becomes unstable as pH rises and leads to formation of trisodium diphosphate, ...
Nilay Ghosh's user avatar
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3 votes
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Why does the titanium go to the tungsten filament in the crystal bar process?

By "gaseous titanium", do you mean "titanium tetraiodide ($\ce{TiI4}$) vapor"? Van-Arkel De-Boer process is a purification process of titanium and zirconium. Basically, what ...
Nilay Ghosh's user avatar
  • 26.3k
3 votes

Heating a mixture of methanol and water?

You need to know the composition of your solution and then look at vapor liquid equilibrium data to find the boiling point of your particular composition solution. See here for boiling point as a ...
J. Ari's user avatar
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3 votes
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Sudden pressure rising in a pipe of an old plant transporting 33% ammonia solution

Ammonia is more soluble at lower temperatures so the temperature change between the outside of the factory and the inside could raise the pressure inside the pipes. Gas dissolved in water are ...
G M's user avatar
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2 votes

Working with typical glass: What temperatures would I be dealing with?

If you want to completely liquefy the glass, you are going to be in the neighborhood of 1400$\ce{^oC}$ to 1700$\ce{^oC}$. A propane torch (not the kitchen sized ones) would allow you to melt small ...
J. Ari's user avatar
  • 1,492
2 votes

How is the process of converting calcium carbonate (CaCO3) into calcium oxide (CaO)?

From wikipedia article of calcium oxide Calcium oxide is usually made by the thermal decomposition of materials, such as limestone or seashells, that contain calcium carbonate ($\ce{CaCO3}$; ...
Nilay Ghosh's user avatar
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2 votes

Main industrial method for producing ethyl ethanoate (acetate)?

According to ACS Molecule of the Week: As you might expect, ethyl acetate was first synthesized from ethanol and acetic acid. The reaction was the classic acid-catalyzed Fischer esterification, ...
Mathew Mahindaratne's user avatar
2 votes

Are there still "prairie dog refineries"?

Any collection of 'hooch stills' that were soldered (?) together would probably have been uneconomical almost as soon as they were built, because welding together a series of serviceable fractional ...
AlaskaRon's user avatar
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