Talk:Concentration

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 Definition In science, engineering and in general common usage: the measure of how much of a given substance there is in a given mixture of substances. [d] [e]
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Many other expressions of concentration

Daniel, as you know, there are quite a few ways to express concentration other than moles per litre. For example:

  • mass per volume (mg/m³, kg/m³, pounds per gallon or lb/gal)
  • parts per million by volume (ppmv) and parts per million by weight (ppmw)
  • molality of solutions, which is moles per mass (mole/kg)
  • mole fraction (moles of component x per total moles)
  • percent by volume (%v) and percent by weight (%w)

Would it not be helpful to mention at least a few of the other ways of expressing concentration? Regards, Milton Beychok 20:06, 29 January 2009 (UTC)

I stick to SI units as far as possible but sure, go ahead. I do not have particular plans for this one, just needed it for Concentration (disambiguation). --Daniel Mietchen 03:38, 1 February 2009 (UTC)

This one sentence article should be merged into Concentration

There is really no reason now to have this one-sentence Concentration (chemistry) article, when that one sentence is actually covered in the much larger and extensive Concentration article.

The one sentence in this article is:

In chemistry, concentration indicates what amount of a substance (measured in units of mole) is present in a given volume of reference (usually measured in units of litres or cubic metres).

The Molarity section, one of the many sections in the Concentration article, states:

Molarity or molar concentration (in units of mol/L) denotes the number of moles of a given solute per litre of solution. The units of mol/L are commonly replaced by the symbol M.
The National Institute of Standards and Technology (NIST) of the United States considers the term molarity and the symbol M to be obsolete and recommends using the term amount-of-substance concentration of B (or concentration of B) and the symbol c with SI units of mol/m3 or other SI acceptable units.[1]. This recommendation has not been universally implemented in academia or chemistry research yet.

Note that Molarity in the Concentration (chemistry) is expressed in the same mol/liter as is defined in this one sentence Concentration (chemistry) article.

If there is no objection forthcoming in the next few days, I will merge this article into Concentration and I will add a new section on Mol per volume so that the merged article will then cover that concentration expression as well. Milton Beychok 05:53, 9 May 2009 (UTC)

Since there have been no objections to the proposed merge, I have made the merge. Milton Beychok 17:38, 13 May 2009 (UTC)
  1. NIST Guide to SI Units NIST website, accessed February 1, 2009. (Scroll down to item 18)