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1500 questions
31
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3 answers
What's a minimal yet chemically-meaningful kinetic system for an oscillating reaction?
Oscillating reactions are a funny aspect of chemistry. I have tried to find various simplified kinetic models of oscillating reactions such as the Belouzov-Zhabotinsky, the Briggs–Rauscher or the Bray–Liebhafsky reactions in order to be able to…
F'x
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31
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3 answers
What is the strongest acid?
According to Wikipedia, $\ce{HeH+}$ and fluoroantimonic acid are the strongest.
According to a News article in Nature, Carborane acid is the strongest, but Wikipedia says fluoroantimonic acid is stronger.
Links:
$\ce{HeH+}$ / Wikipedia - stating…
NeilRoy
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31
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5 answers
How do orbitals coexist with a nucleus?
Many diagrams of orbitals I've seen involve electrons moving through a center point—where the nucleus is. How can this be? Clearly they don't actually pass through the nucleus, so what does happen?
Tuesday
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Why does lemon juice reduce the "fish" odor of sea food — specifically fish?
In studying amines, I read that lemon juice is also used to wash fish because it reacts with the amines on and in the fish to convert the amines to its salt, just reducing the "fishy smell".
I was thinking that it must be the citric acid in lemon…
Winter Soldier
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31
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What is the unit of pH?
I'm making some graphs and I have to label the axes. I want to be extra careful and put the units in even though the meaning of $\text{pH}$ is well known. But I have a problem (though a simple one): $\text{pH}$ is a minus logarithm (base 10) of…
studen
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1 answer
Electrical conductivity of graphite
On this Wikipedia page, the electrical conductivity of various materials are given in the third column ($\sigma \text{ (S/m) at 20}^\circ \text{C}$). I am interested in the entry for Carbon (graphite):
$2$ to $3 \times 10^5 \text{ S/m} \perp…
Andrew
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1 answer
Why is fluorine a gas, but lithium isn't?
$\ce{F2}$ is a gas, but pure lithium is a solid metal. Why is this? Lithium is much lighter, just 3 protons and 3.9 neutrons (average). Fluorine is much heaver, 9 protons and 10 neutrons.
DrZ214
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3 answers
Why are noble gases stable
I was recently asked the question "Why are noble gases stable? with the expectation of providing an answer beyond the general explanation of "they have full valence layers" and I couldn't think of one.
I would love to hear a full description of the…
Chris
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1 answer
An introduction to "oxidation state"/"oxidation number"
I just can't get my head around oxidation states. They're really confusing! Why do I need to assign a number to some element?
What are oxidation states?
How and why should we assign oxidation states?
Are oxidation states real?
M.A.R.
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30
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3 answers
What metals aren't dissolved in/attacked by aqua regia?
Aqua regia (Latin: Royal Water) is one of the strongest acids known in Chemistry, and is capable of dissolving gold and platinum.
My copy of the Oxford science dictionary goes on to say (under the entry: Aqua regia) that metallic silver does not…
paracetamol
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30
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9 answers
What are oxidation states used for?
When I took high school chemistry many years ago, considerable effort was spent on teaching us to compute oxidation states of atoms in various compounds, following a set of rules that looked somewhat arbitrary to me at the time. As far as I…
hmakholm left over Monica
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What is the difference between dynamic and static electronic correlation
I am confused. In the static correlation, we use combination of Slater determinants to account for electronic correlation (known as CI or configuration interaction) and the wave function is represented as a sum of various SD where the HF SD is the…
Osman Mamun
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1 answer
Imaginary Bonding Interactions
Usually in chemistry, we deal with bonding interactions. That is, if I have the diatomic A-A molecule or A-B molecule, there's a favorable interaction (i.e., a bond) and a prototypical MO diagram like this:
As I'd say in a lecture, one orbital goes…
Geoff Hutchison
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30
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3 answers
Are graphite and hexagonal boron nitride aromatic
Are graphite and hexagonal boron nitride aromatic?
Graphite has a planar network of 6-membered rings with each carbon connected to three other carbons. Since the valency of carbon is not satisfied, there will be some $\pi$-bonds. Can graphite act…
Aditya Dev
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30
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4 answers
Why do transition elements make colored compounds?
Why do transition metals element make colored compounds both in solid form and in solution? Is it related to their electrons?
lambda23
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