Questions tagged [notation]
A system of written symbols used to represent qualities or quantities, elements or molecules, or formulas in general. Usually a notation follows a convention or a guideline, often published by IUPAC-IUPAP. This tag should be used for questions regarding the proper use of a notation or misleading or uncommon notation in the scientific literature. Do not confuse this tag with the [nomenclature] or [terminology] tags.
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When writing the net ionic equation, if one of the products ionizes, what is the most appropriate way to account for this in the answer?
Take these two practice problems and their solutions from Ebbing (8th ed) that involve completing the molecular equation, then writing the net ionic equation:
4.42a: $\ce{Ca(OH)2(aq) + 2H2SO4(aq) ->...
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Three stacked arrows, what does it signify?
I was checking the mechanism for the Lossen Rearrangement, when I came across the chemical reaction denoted as follows:
I couldn't find any resource where this notation was talked about.
What do the ...
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What does A. R. in A. R. sodium nitrite mean?
I'm reading about a reaction from a 1970s organic chemistry book. It references A. R. sodium nitrite. What does the A. R. mean?
I see from online that "Ar" means aromatic ring. Is that the ...
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Writing water as a reactant in acid/base dissociation (Brønsted Lowry)?
The dissociation of $\ce{HCl}$ in water is written as:
$$\ce{HCl (aq) -> H+ (aq) + Cl- (aq)} \tag{1}$$
Sometimes we also include $\ce{H2O}$ as a reactant to stress the fact that the protons are not ...
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Rules to follow while writing a chemical formula for polyatomic ions
In Science, textbook for class IX, chapter $3$ [1,p.38], it states:
The rules that you have to follow while writing a chemical formula are as follows:
in compounds formed with polyatomic ions, the ...
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What does K° signify in this reaction?
What does the K° signify in the above reaction. Is it just a typo, or is it supposed to symbolize something?
EDIT: This screenshot is from the solutions manual. In the original textbook, the author ...
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Convention in electrochemical cell notation
While writing the cell notation for a cell, doesn't one have to write the two states in which a species exists in a sequence appropriate to the reaction in which they participate?
For example, in the ...
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Proper notation of doubly charged ions
I have always notated doubly charged ions with a superscript $++,$ such as $\ce{He^{++}}.$ For more highly-charged ions I would denote them with the number of charges, such as $\ce{Pt^{4+}}.$
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How to identify if a material is perovskite or not?
This is more of a materials science question, but I believe many of you have referred NIST Inorganic Crystal Structure Database (ICSD) database.
I am collecting a database of perovskite materials and ...
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What is the "‡" symbol meaning in a reaction mechanism?
I was studying hydroboration from Clayden's Organic Chemistry [1, p. 1281] and the transition state had “‡” symbol in the upper right corner of the activated complex:
We know that this is not the ...
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What is the correct electron dot notation of carbon?
My book says that the dot notation for Lewis structure of carbon has 2 possible ways:
two dots on the right, one on the top, one on the left
one dot on all four sides
Why are both of these correct? ...
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Notation in atomic structure
In the book, The theory of atomic structure and spectra, Robert D. Cowan says that the allowed terms of $p^2$ are $^1S$, $^1D$, $^3P$ and so the possible terms of $p^2 + p\quad$ (obtained by using the ...
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Writing a organic reaction in different form
Can I write this reaction
$$\ce{A + B ->[\ce{X}] C + D ->[\ce{Y}] E + F}$$
as
$$\ce{A + B ->[\ce{(1) X}][\ce{(2) Y}] E + F}$$
Can I write any organic reaction in this way or are there any ...
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Connection between irreducible representations and electronic states in diatomic molecules
I am trying to understand the connection between irreducible representations and molecular electronic states.
To explain the problem: I found some potential energy curves (PECs) for $\ce{N2+}$ in the ...
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How do I denote a measurement with a margin of error using ±?
I am trying to express a quantity that is measured to be $\pu{0.75 mL}$, but could be anywhere between $\pu{0.7 mL}$ and $\pu{0.8 mL}$. Is this the correct way to do it?
$$\pu{0.75 mL} \pm \pu{0.05 ...
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