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38
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3 answers
IUPAC nomenclature: "Smallest sum of locants"?
While naming any compound, the numbering should be done such that position of substituted groups gives smallest sum.
I'm struggling with the IUPAC naming for cyclic compounds. How exactly does this rule work?
Christopher
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38
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4 answers
What exactly is happening when sodium, potassium, or other alkali metal explodes in water?
There are lots of videos on YouTube showing sodium, potassium, etc. exploding when dropped into water (this, for example).
I understand that when an alkali metal is exposed to water, a violent exothermic reaction occurs where a hydroxide and…
bwDraco
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38
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3 answers
Why does basicity of group 15 hydrides decrease down the group?
In my textbook it is written that the order of basic strength of pnictogen hydrides is
$$\ce{NH3 > PH3 > AsH3 > SbH3 > BiH3}$$
I tried but could not find any explanation as to why this happens. What is the explanation?
Soham
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38
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1 answer
Relativistic effect: d-electrons in metallorganic complexes
With higher period the d-electrons of the metal are less strong bonded and therefore oxidative addition is easier for $\ce{Ir(I)}$ than for $\ce{Rh(I)}$ and much easier than for $\ce{Co(I)}$.
For metal carbonyl hydrides, electrons with higher period…
laminin
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37
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1 answer
Single-molecule magnet with electrically-controlled permeability: How does the Titan Shield from Deus Ex work?
In a recent installment of Deus Ex game series there is an augmentation called "Titan Shield" (it has nothing to do with $\ce{Ti}$ element):
A neodymium skin underlay matrix built of nano-meshed rare earth magnets and powered with hook-ins to the…
andselisk
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37
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5 answers
A glass of water with ice-cubes in it. Where's the water the coldest; at the top or bottom?
Suppose that I fill a glass with ice water. As the ice melts, it cools the water around it. Given that cold water is denser than hot water, I would presume that the cold water would sink to the bottom … but it would warm as it sinks, reducing the…
ND Geek
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37
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3 answers
Can hot food ever emit x-rays or gamma rays?
I was just wondering, if heating food up is the result of increasing the energy of bends and stretches in the bonds of the molecules, is it ever possible for tiny amounts of x-rays and gamma rays be emitted?
When we give a molecule enough energy,…
user314901
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37
votes
4 answers
What is actually the difference between valence bond theory and molecular orbital theory?
Recently I have read about both of the concepts in my book (Physical Chemistry by Atkins, Paula). It was literally a reading; though I could understand the language and superposition of orbitals, inversion symmetry, and so on, I never could really…
user5764
37
votes
1 answer
Why super glue does not stick inside their own bottle?
We usually use super glue to stick any two objects but I was wondering like why don't they stick inside their own bottle ?
Shashank
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37
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1 answer
Is the ammonium substituent (-NH3+) really meta-directing in electrophilic substitution?
If we make a resonance structure for the anilinium ion, with positive charge at either the ortho or the para position, we get a pentavalent nitrogen, which is not possible. So, how is the $\ce{-NH3+}$ group meta-directing in electrophilic aromatic…
ravi
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37
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6 answers
May I treat units (e.g. joules, grams, etc.) in equations as variables?
Suppose I have two units, Tonks, $T$, and Borks, $B$, as well as the equation $\frac{50T}{20B}=x$. May I manipulate the equation as though $T$ and $B$ were the kinds of symbols that we learned to manipulate in math class? For…
Hal
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37
votes
2 answers
What are the meanings of dotted and wavy lines in structural formulas?
So I came across this diagram,the other day:
As a chemistry student, I am well-versed with the dashed and wedged lines, but I was wondering what the wavy and the dotted line represent?
arkin
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37
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1 answer
What would follow in the series sigma, pi and delta bonds?
I realise, that this question is a stretch, but I was wondering, how would a bonding orbital be called if it was formed from two $f_{x(x^2−3y^2)}$ or $f_{y(3x^2−y^2)}$ orbitals. Have there been any suggestions on this, was it anywhere proposed or…
Martin - マーチン
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37
votes
5 answers
Why don't the electrons move through the electrolyte (instead of the circuit) in a galvanic cell?
I was learning about galvanic cells and I had a problem understanding why electrons do not travel through the electrolyte solutions themselves, instead preferring to travel through metals. Can electrons travel through an electrolytic…
Xman
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37
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4 answers
Is pyrene aromatic despite failing Hückel's rule?
Pyrene doesn't seem to be aromatic. However, sources claim that it is aromatic.
Considerations:
Pyrene is cyclic. ✓
Pyrene is flat (planar). ✓
Pyrene has 16 π electrons.
Every atom in the ring structure of pyrene is $\ce{sp^2}$ hybridized.…
Dissenter
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