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The contents of the Volume percent page were merged into Volume fraction on 16 October 2015. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
Is it a measurable quantity in non-ideal mixtures? It seems that is only calculable by knowing mass or amount fraction and densities of pure components.-- 188.26.22.131 ( talk) 10:47, 9 September 2013 (UTC)
A question about the index to V-i(j) arises whether or not should be different in the denominator compared to that in numerator of the fraction. I think the index should be identical because the volume of a component is divided by the sum of volumes of all components before mixing.-- 188.26.22.131 ( talk) 15:30, 4 March 2014 (UTC)
If one want to consider , one has simply to substitute j by 1 in
On the other hand, although
is formally correct, a good mathematical experience is needed for understanding that only the index in the numerator has to be substituted by 1. Thus, having the same index in the numerator and in the denominator is confusing for most readers. D.Lazard ( talk) 11:55, 17 March 2014 (UTC)
Certainly the notation uses the same letter, i, for two different things. The i in the numerator stays fixed while the i in the denominator runs through a list of values. This kind of thing actually does leead to mistakes by students in some contexts; I've seen it in papers I've graded.
Michael Hardy (
talk) 17:50, 18 March 2014 (UTC)
Volume percent into volume fraction; Mass percent and Mole fraction already readirect to Mass fraction and Mole fraction, respectively. Fgnievinski ( talk) 18:14, 31 January 2015 (UTC)
Yeah, except that Volume percent is typically concentration, not fraction (that difference does not exist for mass fraction). — Preceding unsigned comment added by 93.199.252.120 ( talk) 18:56, 1 November 2017 (UTC)
One can notice a discrepancy between the volume percent and volume fraction.-- 109.166.132.159 ( talk) 23:12, 20 August 2019 (UTC)
From the NIST Guide to SI, sec. 7.10.2 %, percentage by, fraction:
Because the symbol % represents simply a number, it is not meaningful to attach information to it (see Sec. 7.4). One must therefore avoid using phrases such as “percentage by weight,” “percentage by mass,” “percentage by volume,” or “percentage by amount of substance.” Similarly, one must avoid writing, for example, “% (m/m),” “% (by weight),” “% (V/V),” “% (by volume),” or “% (mol/mol).” The preferred forms are “the mass fraction is 0.10,” or “the mass fraction is 10 %,” or “wB = 0.10,” or “wB =10 %” (wB is the quantity symbol for mass fraction of B—see Sec. 8.6.10); “the volume fraction is 0.35,” or “the volume fraction is 35 %,” or “ φB = 0.35,” or “φB = 35 %” (φB is the quantity symbol for volume fraction of B—see Sec. 8.6.6); and “the amount-of-substance fraction is 0.15,” or “the amount-of-substance fraction is 15 %,” or “xB = 0.15,” or “xB = 15 %.”
and sec 7.4 Unacceptability of attaching information to units:
When one gives the value of a quantity, it is incorrect to attach letters or other symbols to the unit in order to provide information about the quantity or its conditions of measurement. Instead, the letters or other symbols should be attached to the quantity. Example: Vmax = 1000 V but not: V = 1000 Vmax Note: V is a quantity symbol for potential difference. [and non-italic V is voltage unit.]
I intend to update the article accordingly. Fgnievinski ( talk) 18:21, 31 January 2015 (UTC)
What is the quantitative expression of the relative volume difference associated to the verbal phrase +/_x % deviation (expansion or contraction) from the addivity of volumes in water ethanol or water salt/sugar solutions?
Could it be a fraction whose numerator include the difference between the volume of the mixture V and the volumes of the two components V1 and V2 and the denominator equals the sum V1+V2:
? or ?
Which one of these two variants of this fraction which can be called relative volume difference are more appropiate?-- 85.121.32.1 ( talk) 15:39, 6 May 2016 (UTC)
The previous section above suggests the approaching of a link to volum apparent molar property in relation to the deviation from additivity.-- 82.137.11.8 ( talk) 13:42, 17 October 2017 (UTC)
A section Volume concentration could be added to article, perhaps expanding the info at talk:Volume concentration with details from de:Volumenkonzentration.-- 109.166.132.159 ( talk) 23:41, 20 August 2019 (UTC)
This
level-5 vital article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||
|
The contents of the Volume percent page were merged into Volume fraction on 16 October 2015. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
Is it a measurable quantity in non-ideal mixtures? It seems that is only calculable by knowing mass or amount fraction and densities of pure components.-- 188.26.22.131 ( talk) 10:47, 9 September 2013 (UTC)
A question about the index to V-i(j) arises whether or not should be different in the denominator compared to that in numerator of the fraction. I think the index should be identical because the volume of a component is divided by the sum of volumes of all components before mixing.-- 188.26.22.131 ( talk) 15:30, 4 March 2014 (UTC)
If one want to consider , one has simply to substitute j by 1 in
On the other hand, although
is formally correct, a good mathematical experience is needed for understanding that only the index in the numerator has to be substituted by 1. Thus, having the same index in the numerator and in the denominator is confusing for most readers. D.Lazard ( talk) 11:55, 17 March 2014 (UTC)
Certainly the notation uses the same letter, i, for two different things. The i in the numerator stays fixed while the i in the denominator runs through a list of values. This kind of thing actually does leead to mistakes by students in some contexts; I've seen it in papers I've graded.
Michael Hardy (
talk) 17:50, 18 March 2014 (UTC)
Volume percent into volume fraction; Mass percent and Mole fraction already readirect to Mass fraction and Mole fraction, respectively. Fgnievinski ( talk) 18:14, 31 January 2015 (UTC)
Yeah, except that Volume percent is typically concentration, not fraction (that difference does not exist for mass fraction). — Preceding unsigned comment added by 93.199.252.120 ( talk) 18:56, 1 November 2017 (UTC)
One can notice a discrepancy between the volume percent and volume fraction.-- 109.166.132.159 ( talk) 23:12, 20 August 2019 (UTC)
From the NIST Guide to SI, sec. 7.10.2 %, percentage by, fraction:
Because the symbol % represents simply a number, it is not meaningful to attach information to it (see Sec. 7.4). One must therefore avoid using phrases such as “percentage by weight,” “percentage by mass,” “percentage by volume,” or “percentage by amount of substance.” Similarly, one must avoid writing, for example, “% (m/m),” “% (by weight),” “% (V/V),” “% (by volume),” or “% (mol/mol).” The preferred forms are “the mass fraction is 0.10,” or “the mass fraction is 10 %,” or “wB = 0.10,” or “wB =10 %” (wB is the quantity symbol for mass fraction of B—see Sec. 8.6.10); “the volume fraction is 0.35,” or “the volume fraction is 35 %,” or “ φB = 0.35,” or “φB = 35 %” (φB is the quantity symbol for volume fraction of B—see Sec. 8.6.6); and “the amount-of-substance fraction is 0.15,” or “the amount-of-substance fraction is 15 %,” or “xB = 0.15,” or “xB = 15 %.”
and sec 7.4 Unacceptability of attaching information to units:
When one gives the value of a quantity, it is incorrect to attach letters or other symbols to the unit in order to provide information about the quantity or its conditions of measurement. Instead, the letters or other symbols should be attached to the quantity. Example: Vmax = 1000 V but not: V = 1000 Vmax Note: V is a quantity symbol for potential difference. [and non-italic V is voltage unit.]
I intend to update the article accordingly. Fgnievinski ( talk) 18:21, 31 January 2015 (UTC)
What is the quantitative expression of the relative volume difference associated to the verbal phrase +/_x % deviation (expansion or contraction) from the addivity of volumes in water ethanol or water salt/sugar solutions?
Could it be a fraction whose numerator include the difference between the volume of the mixture V and the volumes of the two components V1 and V2 and the denominator equals the sum V1+V2:
? or ?
Which one of these two variants of this fraction which can be called relative volume difference are more appropiate?-- 85.121.32.1 ( talk) 15:39, 6 May 2016 (UTC)
The previous section above suggests the approaching of a link to volum apparent molar property in relation to the deviation from additivity.-- 82.137.11.8 ( talk) 13:42, 17 October 2017 (UTC)
A section Volume concentration could be added to article, perhaps expanding the info at talk:Volume concentration with details from de:Volumenkonzentration.-- 109.166.132.159 ( talk) 23:41, 20 August 2019 (UTC)