12
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How to understand the chemical formula of Prussian blue complex w.r.t its crystal structure?
The structure of Prussian blue is not as regular as Jonas thought. It is basically cubic as Jonas has drawn. But Jonas's figure includes the same number of $\ce{Fe^{II}}$ as $\ce{Fe^{III}}$, which is ...
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9
votes
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Where is the negative charge localized in tetrazolate ion?
(Final update at end - TLDR: I did a Bader aka Atoms in Molecules analysis)
I did a quick run with CRYSTAL23, a local basis set code that concentrates on periodic structures rather than isolated ...
- 3,154
7
votes
What is the chemical formula of ghee?
The composition of ghee varies depending on the animal whose milk has been used. Ghee is a complex lipid of glycerides (majorly triglycerides), free fatty acids, phospholipids, sterols, sterol esters, ...
- 26.3k
7
votes
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What is the maximum number of water molecules that has been recorded till date to present as water of crystallization in a compound?
It might be a protein crystal. Proteins are large and the interstitial space is filled to a large extent with water. The volume of a protein crystal occupied by the solvent can be 50% or so. However ...
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7
votes
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Empirical formula and rounding
In the part where we have to multiply by subscripts to make them integers, are there clear rules?
No. The number of significant figures in the given data can give some guidance. If there is a large ...
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6
votes
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What is the chemical composition of Ferrous Ferrocyanide?
It is not common to find the ferrous ferrocyanide because it oxidizes rapidly. As you can see the remaining salts or pigments are pretty stable in air. This one is white. I quote from a very old ...
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6
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What is the maximum number of water molecules that has been recorded till date to present as water of crystallization in a compound?
This feels like cheating, since andselisk did all the hard work already and could have provided you with the answer, but I would think
$$\ce{Na48[H_xMo368O1032(H2O)240(SO4)48] · \text{ca.}~1000 H2O}$$
...
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6
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How can I mix methylene chloride, methanol and hydrofluric acid to make a paint stripper?
It is not clear how reliable the concentrations given in the SDS are. It is not uncommon to give a range, but actually manufacture product at one end of the range.
I would take 25 parts of methanol ...
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5
votes
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How to write formula for potassium hydrogenpyrophosphite?
As phosphorous acid is biprotic:
$$\ce{HO-PH(=O)-OH},$$
the respective pyrophosphorous acid is biprotic too:
$$\ce{HO-PH(=O)-O-PH(=O)-OH}$$
and pyrophosphite is:
$$\ce{^{-}O-PH(=O)-O-PH(=O)-O-}$$
...
- 42.7k
5
votes
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What does the dot indicate in the molecular formula for white lead?
It could be as well written as $\ce{Pb3(OH)2(CO3)2}$.
The formula $\ce{2 PbCO3 . Pb(OH)2}$ is used as better visualization of composition being an intermediate between lead carbonate and lead ...
- 42.7k
5
votes
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What does ‘(A)’ mean in SMARTS pattern when using Chemicalize to draw the chemical structure?
According to Daylight Chemical Information Systems — SMARTS Theory Manual and Chemaxon docs — SMARTS, the capital letter ‘A’ in SMARTS notation is a label for an aliphatic primitive (atom).
Chemaxon’s ...
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4
votes
Are atom coordinates in molfile necessary to produce a valid InChI identifier
Quoting from "InChI, the IUPAC International Chemical Identifier" article [Heller et al. Journal of Cheminformatics (2015) 7:23]:
Each atom is described by a number of properties: its
...
- 203
4
votes
Si(OH)4 vs. H4SiO4 vs. SiO2.2H2O
First, my answer here is relevant: What is chemical formula of Bauxite?, and also follow links inside.
Regarding your question specifically, there is not much difference. However, there are some ...
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4
votes
How is Potassium present in Potato (form) and where does it come from originally?
Whoever told you that boiling a potato can reduce potassium has told you a fake story. You cannot evaporate potassium ions.
Potassium ion also comes from the natural soil minerals and it exists as ...
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4
votes
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What's the difference between Zinc Ascorbate and Zinc Gluconate?
As I understand your question, “the two” refers to Zinc Gluconate and Zinc Ascorbate.
Zinc gluconate and zinc ascorbate are distinctly different compounds. They are both adducts of Zn with one Zn and ...
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3
votes
Is there a concise way to calculate pH of a solution after being diluted with water?
The calculation will depend on whether the chemical of interest predominantly behaves as an acid or a base, whether it's strong or weak, and whether it's monoprotic or polyprotic.
Concentrated pure ...
- 1,749
3
votes
Why is Pb3O4 called lead(II,IV) oxide?
@Poutnik gave us the Wikipedia link which basically contains the answer:
Lead tetroxide ("red lead"), a mixed oxide with formula $\ce{Pb3O4}$, may be thought of as lead(II) ortho-plumbate(...
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3
votes
Reaction between NaCl and NaHCO3
Use other online databases, unless you have misinterpreted the database info. Quoting the info would help.
Mixing $\ce{Na2CO3}$ and $\ce{HCl}$ leads to the possibly violent reaction releasing big ...
- 42.7k
3
votes
Using the mole ratio to figure out the molecular formula
There is $0.008$ moles of $\ce{PO4^{3-}}$ ions. So the total number of negative charges is $3·0.008 = 0.024$ moles. This number must be equal to the number of positive charges. Let's check it.
As ...
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3
votes
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Sucrose skeletal formula - missing Carbon and Hydrogen
Since your chemistry lessons date back about 15 years, I'd loke to refreash your organic chemistry knowledge. You may need to be aware that carbon can make maximum if 4 single bonds. Therefore, when ...
3
votes
Separating Silica from silicates
Mechanically speaking, it is not possible to separate $\ce{SiO_2}$ from these minerals. The only way to do it is carrying out a chemical transformation. Here is an example of such a treatment.
Mix a ...
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3
votes
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Glutaraldehyde or Glutardialdehyde
Many articles I've read, just mention glutaraldehyde, not glutardialdehyde.
Not only Merck, but also Sigma-Aldrich listed glutardialdehyde (25% solution) and glutaraldehyde (25% solution) under the ...
3
votes
betamechaptoethanol smell
Some sulfur organic compounds have rather a strong odor. For your delectation, may I suggest reading Derek Lowe on the not dissimilar compound, thioacetone. For further documentation, see Grayson Van ...
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3
votes
Accepted
The formula of ammonium phosphomolybdate
The simplest way of writing the formula of ammonia phosphomolybdate is the Brutto formula, $\ce{(NH4)3[PMo12O40]}$. The phosphomolybdate ion is a polyoxometalate but we tend to stick with $\ce{[...
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2
votes
What's the chemical reaction between coffee and sodium bicarbonate?
Per a source, to quote:
Here are the nine major acids in coffee, listed from highest concentration to lowest: chlorogenic, quinic, citric, acetic, lactic, malic, phosphoric, linoleic, and palmitic (3)...
- 5,582
2
votes
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Lewis structures and chemical-compound formulas
The elements in the third period of the periodic table has following electron configurations and they achieve their most stable ionic forms by gaining or losing indicated electrons (final electron ...
2
votes
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Finding formula of reduced scandium oxide using its mass and mass of obtained metal
Since scandium oxide is an ionic compound, the method is exactly the same as obtaining the empirical formula, from the ratio of the amounts of elements $n(\ce{Sc})$ and $n(\ce{O}).$
$$n(\ce{Sc})=\frac{...
- 527
2
votes
Are there examples of molecular formulas with nested groups?
The closest I could find is mixed cation-anion salt:
$\ce{NaM2[PuO4(OH)2]·4H2O}$ where $\ce{M = Rb,Cs}$ and
$\ce{NaRb5[PuO4(OH)2]2·6H2O}$.
$\ce{(NO)_{0.25}(NO2)_{0.75}Cu(SbF6)3}$, $\ce{(H3O)_{0.125}(...
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2
votes
Accepted
Are there examples of molecular formulas with nested groups?
Too long for a comment: Chemical formulas for polymers can utilize nested enclosing glyphs but, from what I've seen, the accepted format is to use parentheses for the inner glyphs, and square ...
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2
votes
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Combustion analysis of hydrocarbon
Let Hydrocarbon be of form $\ce{C_xH_y}$
Our combustion reaction becomes $\ce{C_xH_y}+(2x+\frac{y}{2})\ce{O_2}\implies x\ce{CO_2}+\frac{y}{2}\ce{H_2O}$
$1$ mole of hydrocarbon produce $x*44g$ of $\ce{...
- 425
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