61
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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 ...
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43
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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 ...
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40
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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 ...
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23
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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 ...
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22
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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 ...
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21
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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, ...
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18
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Why is the Haber process carried out at such high temperatures?
As others have pointed out, it is purely kinetics, but you may still wonder, why.
For a reaction to actually occur (in both directions) and thus for an equilibrium to be reached, you need to overcome ...
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16
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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 ...
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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 ...
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Why is the Haber process carried out at such high temperatures?
The answer mainly has to do with kinetic considerations, as aml points out. I want to point out another thing.
In a typical industrial setting, you don't just mix the $\ce{N2}$ with the $\ce{H2}$ at ...
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12
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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? ...
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7
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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 ...
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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 ...
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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 ...
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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 ...
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4
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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 ...
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4
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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 ...
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Why is the Haber process carried out at such high temperatures?
While it is true that the Haber Process would be much more efficient at a lower temperature it's carried out at a higher one because it happens much faster at the higher temperature and while the ...
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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
...
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4
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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 ...
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4
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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 ...
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4
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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 ...
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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, ...
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3
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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 ...
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3
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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 ...
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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 ...
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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 ...
2
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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 ...
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Only top scored, non community-wiki answers of a minimum length are eligible