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25
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3 answers
How does one tell if a specific molecule is acidic or basic?
Let's take the $\ce{KOH}$ molecule into account. I know it is a base from literature, but how would one go about determining if a molecule is acidic or basic simply based on the structure of the molecule? How about amphoteric?
Also, I understand…
2567655222
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What single, pure compound would best replace petrol?
Petrol for use as automotive fuel is produced by blending of different product streams of oil refining. It consists of hundreds of different compounds, and the exact composition can vary widely. Certainly, not all components are absolutely…
user7951
25
votes
2 answers
Why does water dissociate to H3O+ and OH- rather than H+ and OH-?
Why does water dissociate to
$\ce{H3O+ + OH-}$
instead of $\ce{H+ + OH-}$?
This question came to surface when I was learning about acids and bases, and learned this definition:
$\mathrm{pH=}-\log_{10}[\ce{H+}]$
Which after looking at Wikipedia,…
Ell
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2 answers
Which is the currently accepted mechanism of a Wittig reaction?
The Wittig reaction is one of the most significant advances in synthetic organic chemistry in the 20th century and rightfully won its discoverer, Georg Wittig, the Nobel Prize in Chemistry.
A Wittig reaction is the addition of a phosphorus ylide…
Jan
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25
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3 answers
What can I do if I don't get a phase separation between my organic and water phases?
Solvent extraction in a separation funnel is a very common method in preparative organic chemistry. But sometimes you don't get a nice phase separation between the organic and the water phase.
What are the possible causes that can prevent the…
Mad Scientist
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25
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2 answers
Is the nomenclature "primary", "secondary", "tertiary", and "quaternary" carbon atoms limited to sp3 carbon atoms?
In organic chemistry we can classify carbon atoms as primary, secondary, tertiary, or quaternary based on the number of additional carbon atoms bonded to the carbon atom of interest. The definitions in the textbook I teach from (Klein, 1st Ed.…
Ben Norris
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25
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1 answer
Why is Diiron nonacarbonyl so exceptional?
My textbook(NCERT) says:
With exception of $\ce{Fe2(CO)9}$, all other metal carbonyls are soluble in hydrocarbon solvents.
Weller, M.; Overton, T.; Rourke, J.; Armstrong, F. Inorganic Chemistry, 6th ed. states:
The most striking exception among…
Nilay Ghosh
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25
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1 answer
Functional difference of Benedict's solution and Fehling's solution
Chemically, Benedict's solution and Fehling's solution are very similar, with copper sulfate as a source of copper (II) ions, sodium carbonate, and sodium hydroxide respectively as alkalis, and sodium citrate and sodium potassium tartarate…
busukxuan
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25
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1 answer
When measuring avidity should you use the ligand concentration or the nanoparticle concentration?
Looking at avidity between a ligand-receptor, you're looking at an enhancement of the $K_d$ compared to a lone ligand.
Is it more appropriate to compare the $K_d$ using the concentration of the "free" ligand or the concentration of the free…
bobthejoe
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25
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6 answers
Why can't rust form without water?
Shouldn't iron oxide be able to form without water? It is just iron and oxygen. I don't really understand what the dot followed by the $\ce{H2O}$ means either. I was reading on wikipedia, but I have a rather terrible understanding of chemistry.…
user1638
25
votes
3 answers
Can heteroatoms with lone pairs be chiral centres?
If a compound has a carbon atom with four different groups covalently bonded to it, it is called asymmetric and enantiomers of the compound can exist.
But imagine if one has a different central atom, such as a nitrogen or a sulfur where one of the…
caconyrn
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25
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1 answer
What software is used to generate the PDB molecule of the month images?
What software does the PDB use to generate these "cel-shaded" protein models with outlines around foreground atoms?
(Leptin: May 2012 Molecule of the Month by David Goodsell)
Nick T
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25
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0 answers
How to calculate transition dipole moment from two known wavefunctions
I am interested in calculating the transition dipole moment (TDM) from the information from two wavefunctions of different states. This is somewhat similar to calculating the molecular dipole moment which was previously answered here:
How to…
brose
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25
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What does "reaction coordinate" mean? What does it mean when a reaction has TWO reaction coordinates?
I'm familiar with the concept of a reaction coordinate from high school chemistry as some generic conformational parameter that all of the intermediate states of a chemical reaction lie upon. Recently, though, I've seen some presentations where…
Dan
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25
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What is the role of sulfuric acid and mercury(II) sulfate in the oxymercuration of alkynes?
I have a homework problem where I'm given a terminal alkyne. The goal of the problem is to choose the reagent that will result in a particular ketone.
Here's a really general view of the reaction I drew out showing the reactants I chose (I don't…
Melanie Shebel
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