Questions tagged [chemical-formula]
For questions related to molecular formula, empirical formula, formula unit, representing the chemical proportions of atoms that constitute a particular chemical compound, molecule, ion, complex, crystal, etc. using chemical element symbols, numbers, and other symbols. NOT related to 'notation', 'composition', 'structure' or 'nomenclature'.
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Is there a concise way to calculate pH of a solution after being diluted with water?
I do not have a chemistry degree or even much knowledge in the subject at all. I'm actually an auto detailer and this is why I have an interest in pH levels. All of our chemicals obviously have pH ...
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Resorcinol turned brown [closed]
I stored resorcinol in a transparent plastic container with an airtight lid. There was some air captured inside the container too. After some days, it turned brown. please tell what happened to it?
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How to get the total number of numbered positions in a molecule/compound
I'm working on a metabolite database where "labeled" compounds can contain isotopically labeled atoms in specific positions. When a new labeled compound is entered into the database, we'd ...
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How do I calculate the empirical formula when ash is present in the percentage composition?
I am trying to calculate a chemical formula. How do I calculate the empirical formula when ash is present in the percentage composition?
Example-
C- 47.7%
H- 7.2%
N- 1.8%
S- 0.9%
O- 38.0%
Ash- 4.4%
...
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Reaction between NaCl and NaHCO3 [closed]
Does NaHCO3 (aq) react with NaCl(aq)? I don't think they should undergo any reaction but in the online database it is showing that they react to form Na2CO3 and HCl. Is it correct?
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Why is Pb3O4 called lead(II,IV) oxide?
We know that iron(II,III) oxide has the formula $\ce{Fe3O4}$ which is a combination of iron(II) oxide and iron(III) oxide with formulas $\ce{FeO}$ and $\ce{Fe2O3}$ respectively.
So why isn't this the ...
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How can the multiplicative number (n) of a chemical series like polyethylene glycol (PEG) be a non-integer?
https://en.m.wikipedia.org/wiki/PEG_400
Down at chemical or molecular formula, it says:
C_2n H_4n+2 O_n+1, like for all polyethylene glycols (PEG)s, but then says n=8.2 to 9.1....
Huh?
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How to find the empirical formula from mass percentages of oxides [closed]
Say you've given an element X and it makes two oxides. The first oxide is $X_\mathrm{4}O_\mathrm{6}$ and the mass percentage of oxygen is 43.7%. In the second oxide, the mass percentage of X is 43.7%.
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Are there examples of molecular formulas with nested groups?
Sometimes a molecular formula is written using groups, for instance $\ce{Al2(SO4)3}$.
Are there examples of formulas with nested groups, such as $\ce{ABC[MNO2(XYZ)4]3}$ or is this avoided?
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Using the mole ratio to figure out the molecular formula [closed]
It takes $\pu{8.0 cm^3}$ of aqueous sodium phosphate to fully react with $\pu{12.0 cm^3}$ of an aqueous solution of the nitrate of metal $\ce{T}$. If both solutions have a concentration of $\pu{1 mol ...
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Combustion analysis of hydrocarbon
Combustion analysis of a hydrocarbon produced 33.01 g CO2 and 4.84 g H2O.
I was asked to find the empirical formula of the hydrocarbon. I used these molar mass values for my calculations:
C - 12.0107
...
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What is the chemical composition of Ferrous Ferrocyanide?
To this day, iron-cyanide complexes confuses me. So, I want to settle this once and for all. After scavenging the internet, I gathered the following result:
$$
\ce{Ferr}
\color{blue}{\ce{ous}}~\ce{...
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How to understand the chemical formula of Prussian blue complex w.r.t its crystal structure?
Note: Just to be clear, I do not refer to "complex molecules" (i.e. "complex" as "complicated"), but to actual complexes.
I am trying to understand the structure of ...
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How can I mix methylene chloride, methanol and hydrofluric acid to make a paint stripper?
HF paint stripper on data sheets lists
Methylene chloride 70>85%
Methanol 10>25%
Hydrofluric acid. 5%
Previously I have found the chemical splits. Is there a particular method to ...
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On basic mercury salts
$\ce{HgCO3.3HgO}$ and $\ce{HgO.Hg(NH2)Cl}$ are called basic mercury carbonate and basic mercury amidochloride, respectively. I found this thread on the former; I've only seen the latter as the product ...
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