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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Where is the negative charge localized in tetrazolate ion?
I am seeing images of tetrazolate ion where the negative charge is placed at different locations:
On the nitrogen atom
Inside the tetrazole ring
or
On the carbon atom
Is there any electronic ...
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What does ‘S/A’ mean in SMARTS pattern when using Chemicalize to draw the chemical structure?
I am still new to the SMARTS annotation. I am wondering what does S/A’ mean on the bond labeling drawn with Chemicalize using SMARTS [!#1]c1n[cH]nc([!#1])c1[!#1]? ...
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What does ‘(A)’ mean in SMARTS pattern when using Chemicalize to draw the chemical structure?
I am not quite sure what ‘(A)’ could mean for the carbon atom when writing the SMARTS CCN(C)C using Chemicalize to draw the chemical structure below. Can anyone ...
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Hydrogen oxidation number
I am aware that since 2005, IUPAC guidelines established that hydrogen is more electronegative than all elements from group V in the periodic table (you can check official documentation). Thus, $\ce{...
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What does the dot indicate in the molecular formula for white lead? [duplicate]
I came across the following molecular formula for white lead: $2\mathrm{Pb}\mathrm{CO3}·\mathrm{Pb(OH)_2}$. What does the center dot indicate here? Is this a non-covalent interaction of some kind? ...
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The formula of ammonium phosphomolybdate
It is written in my qualitative chemistry textbook that phosphate could be tested by introducing phosphate, nitric acid and ammonium molybdate which gives (NH4)3H4[P(Mo2O7)6].
I found out in the ...
user139387
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Hydrogen Peroxide 60% Dilution [closed]
Can anyone please help me? I have used various 'dilution' calculators' online, and done the equations on paper. However I DO NOT want to get this wrong and one can be great at math, but help and ...
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Minimum molar mass of organic compound with given mass fraction of carbon
Problem from my coaching module:
An organic compound X contains 10% C by mass. The minimum molar mass of compound X is (in g/mol)
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I think the compound must have an integer amount of ...
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Position of H in formula [closed]
I couldn't come to a resolution with these 2 questions that use hydrogen in the middle of a formula that is equipped with a numerical prefix.
Why is is one inside the bracket and one outside? Am I ...
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How's the formula mass of a molecule calculated? Is it the mass in it's empricial formula or molecular formula? [closed]
Like glucose, butane and benzene. How would you calculate their formula mass? Would you calculate it as the mass of their empricial formula or their molecular formula (basically same as molecular mass)...
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betamechaptoethanol smell [closed]
I am doing my masters in science and today one of our neighbors from the other lab came to heat his samples on a heating pad. the samples were in small tubes which contained Betamechaptoethanol, when ...
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Glutaraldehyde or Glutardialdehyde
Recently I was searching for a chemical compound to meet my research needs, i.e. glutaraldehyde, and later I found that Merck has been released different name of compound: (1) glutaraldehyde and (2) ...
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Empirical formula and rounding
I am very confused with the procedure to find the empirical formula. In the part where we have to multiply by subscripts to make them integers, are there clear rules?
For example, if I have the ...
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Number of neutrons in a chemical question?
Consider the equation $\ce{H2 + H2+ -> H + H3+}$
What is the atomic structure of the $H_3^+$ ion? I understand that the H$_3^+$ ion contains 3 protons and 2 electrons. However, how many neutrons ...
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How to write formula for potassium hydrogenpyrophosphite?
I know that pyrophosphite by itself is $\ce {({P_2}{O_5})^{4-}}$. My question is about the hydrogen part- how to know how many hydrogens to add? The answer key for this question says the compound is $\...
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