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The following sections are tangential to the subject of calorimetry. --[[User:Eequor| η♀ υωρ]] 15:12, 18 Sep 2004 (UTC)
I notice this unusual structure of subsections in this section. What are the differences in wikimark-up?-- 5.2.200.163 ( talk) 10:22, 22 October 2015 (UTC)
Main article: Heat.
Heat is an amount of energy which is usually linked with a change in temperature or in a change in phase of matter. The SI unit for heat is the joule.
The equation for measuring heat is:
Main article: Mechanical work.
Work is the energy transferred in applying force over a distance. In calorimetry, the force is generally pressure and instead of distance, volume is used. Work is given by the formula:
Main article: Internal energy.
Internal energy is the kinetic energy associated with the motion of molecules, and the potential energy associated with the rotational, vibrational, and electric energy of atoms within molecules. Internal energy is a quantifiable state function of a system.
Internal energy can not be measured directly; it is only measured as a change (ΔU). The equation for change in internal energy is:
Main article: Enthalpy.
Enthalpy is the sum of the internal energy of matter and the product of its volume and the pressure.
Enthalpy is defined by the following equation:
The total enthalpy of a system cannot be measured directly; the enthalpy change of a system is measured instead. Enthalpy change is defined by the following equation:
It appears the history alluded to in the article [at the bottom] is the history of a company that makes lab products, not a history of calorimetry. In fact, when I looked at the history page, I saw almost nothing pertaining to the history of calorimetry?
Is it possible someone just wanted free advertising? Should we snip it?
Phantym 21:24, 24 May 2005 (UTC)
The article currently claims If an object is isolated from the rest of the universe, its temperature must stay constant.
I suspect this is incorrect. If I take this small, inert rock at room temperature, and stick it far out past the orbit of Pluto, its temperature would plummet, right? What about the heat pad mentioned in the supercooling article? Imagine that I pull the pin from a grenade, then isolated that grenade from the rest of the universe. The temperature of that grenade rapidly rises when it eventually blows up, right? -- DavidCary 03:33, 22 September 2005 (UTC)
If a system has several energy states at a given temperature, calorimetry can be used to dissect the number and energy of the different states, right? That would be a nice thing to add here. -- Dan| (talk) 09:38, 15 March 2006 (UTC)
I got some references here (specific to protein folding / folding intermediates), which may be a start for this section...
HTH -- Dan| (talk) 09:58, 15 March 2006 (UTC)
Any objections if I add a paragraph on flow calorimetry? I'll put a draft in discussion, or on my talk page before adding it. Alanf777 ( talk) 18:04, 28 November 2011 (UTC)
The page on CALORIMETRY is not good. It is far too theoretical and will only serve to scare people away from calorimetry. There are at least a dozen different calorimetric techniques (DSC, adiabatic calorimetry, semi/quasi-adiabatic, heat conduction, radiation detectors, flow calorimetry etc etc) that need to be described at the start so that the reader can decide which technique he/she is interested in. Now - after a few lines of general information - the reader meets a complex text and a lot of math which is complex and very limited with respect to what calorimetry is in general. For example, after the figures the text is "Calorimetry requires that the material being heated have known definite thermal constitutive properties...". This is not true for at least two reasons: 1. In most calorimetric techniques the sample is not heated. 2. Calorimetry is just a collection of measurement techniques; they work - more or less well - on all materials. One of the advantages of the calorimetry (heat conduction) that I work with is that it is not dependent on the properties of the samples (solid/liquid/gaseous, transparent/opaque, surface area etc). I have worked with calorimetry for about 20 years and I have never used the equations that make up 95% of this page. I may come back and try to do something here when I have time, but I do not know where to start... . — Preceding unsigned comment added by Larswa ( talk • contribs) 13:23, 2 March 2014 (UTC)
I undid this good faith edit. It was too specialized for the place where it went in the lead. Besides constant pressure calorimetry, there are also forms of calorimetry with constant volume, and with constant temperature. Chjoaygame ( talk) 18:11, 21 October 2015 (UTC)
I think a section about nuclear calorimetry is a very useful addition to article. This proposal is made given the aspects analyzed on talk:standard enthalpy of formation and talk:Hess's law especially about the heat of neutron capture reactions and its consequences on applying Hess law in calculating the heat of formation of isotopes like deuterium D(2) which seems to generate inconsistencies between various (standard thermochemical) assumptions like D2 heat of formation beeing considered zero by NIST tables.-- 5.2.200.163 ( talk) 10:15, 22 October 2015 (UTC)
My opinion is that nothing should be inserted on nuclear calorimetry unless sources are given. Much of the above discussion is based on 5.2.200.163's opinion of what seems reasonable, but both Chjoaygame and I have presented objections to his/her reasoning, and Wikipedia policy is not to include disputed material without sources. I do not think it necessary to repeat the whole argument again. Dirac66 ( talk) 18:02, 31 October 2015 (UTC)
Editor Chjoaygame has objected above to the sentence It [Hess's law] applies to the special case of paths consisting of chemical reactions (or changes of state) at constant temperature and pressure. I think this is just a case of sloppy wording. Chjoaygame has interpreted It applies ... as It must be at constant T and p, which I agree would be incorrect here. But I think what was meant is It is usually applied to, which just means that most applications of Hess's law consider the case of constant T and p for convenience, and does not imply that the law is invalid for other cases. I will change the wording of that article accordingly. Dirac66 ( talk) 18:02, 31 October 2015 (UTC)
I think the new section of the present article is OK now. I am not sure what you mean by the heat-or-reaction task. If you mean the Hess's law article which we were discussing above, I have just added a sentence linking it to the present article, so that readers of Hess's law can find the experimental details here. Dirac66 ( talk) 02:00, 2 November 2015 (UTC)
I don't Wikipedia's guidelines for which pages can get pronunciation guides is, but if this one applies, it should probably get one. When I was researching this topic, I first thought it was pronounced /kəˈlor.ɪ.mɛt.ri/, and asked some other people, who had not heard the term before. I looked to the wikipedia page, but it had nothing, so I had to use something like howtopronounce.com, but those kinds of sources never have IPA for whatever reason. I eventually found out that the correct pronunciation is something like /kæ.ləˈrɪm.ə.tri/ . It would be helpful if this was in the beginning of the article.
A few month ago, i created the article Richmann's law, which was the first equation for calorimetric calculations and should therefore be mentioned here. My english is to bad, to write in a proper scientific language. Maybe someone else can implement it and double check the new article. Thank you and greetings from german wikipedia. LukeTriton ( talk) 06:13, 31 January 2023 (UTC)
![]() | This ![]() It is of interest to the following WikiProjects: | |||||||||||||||||||||||||||||||||
|
The following sections are tangential to the subject of calorimetry. --[[User:Eequor| η♀ υωρ]] 15:12, 18 Sep 2004 (UTC)
I notice this unusual structure of subsections in this section. What are the differences in wikimark-up?-- 5.2.200.163 ( talk) 10:22, 22 October 2015 (UTC)
Main article: Heat.
Heat is an amount of energy which is usually linked with a change in temperature or in a change in phase of matter. The SI unit for heat is the joule.
The equation for measuring heat is:
Main article: Mechanical work.
Work is the energy transferred in applying force over a distance. In calorimetry, the force is generally pressure and instead of distance, volume is used. Work is given by the formula:
Main article: Internal energy.
Internal energy is the kinetic energy associated with the motion of molecules, and the potential energy associated with the rotational, vibrational, and electric energy of atoms within molecules. Internal energy is a quantifiable state function of a system.
Internal energy can not be measured directly; it is only measured as a change (ΔU). The equation for change in internal energy is:
Main article: Enthalpy.
Enthalpy is the sum of the internal energy of matter and the product of its volume and the pressure.
Enthalpy is defined by the following equation:
The total enthalpy of a system cannot be measured directly; the enthalpy change of a system is measured instead. Enthalpy change is defined by the following equation:
It appears the history alluded to in the article [at the bottom] is the history of a company that makes lab products, not a history of calorimetry. In fact, when I looked at the history page, I saw almost nothing pertaining to the history of calorimetry?
Is it possible someone just wanted free advertising? Should we snip it?
Phantym 21:24, 24 May 2005 (UTC)
The article currently claims If an object is isolated from the rest of the universe, its temperature must stay constant.
I suspect this is incorrect. If I take this small, inert rock at room temperature, and stick it far out past the orbit of Pluto, its temperature would plummet, right? What about the heat pad mentioned in the supercooling article? Imagine that I pull the pin from a grenade, then isolated that grenade from the rest of the universe. The temperature of that grenade rapidly rises when it eventually blows up, right? -- DavidCary 03:33, 22 September 2005 (UTC)
If a system has several energy states at a given temperature, calorimetry can be used to dissect the number and energy of the different states, right? That would be a nice thing to add here. -- Dan| (talk) 09:38, 15 March 2006 (UTC)
I got some references here (specific to protein folding / folding intermediates), which may be a start for this section...
HTH -- Dan| (talk) 09:58, 15 March 2006 (UTC)
Any objections if I add a paragraph on flow calorimetry? I'll put a draft in discussion, or on my talk page before adding it. Alanf777 ( talk) 18:04, 28 November 2011 (UTC)
The page on CALORIMETRY is not good. It is far too theoretical and will only serve to scare people away from calorimetry. There are at least a dozen different calorimetric techniques (DSC, adiabatic calorimetry, semi/quasi-adiabatic, heat conduction, radiation detectors, flow calorimetry etc etc) that need to be described at the start so that the reader can decide which technique he/she is interested in. Now - after a few lines of general information - the reader meets a complex text and a lot of math which is complex and very limited with respect to what calorimetry is in general. For example, after the figures the text is "Calorimetry requires that the material being heated have known definite thermal constitutive properties...". This is not true for at least two reasons: 1. In most calorimetric techniques the sample is not heated. 2. Calorimetry is just a collection of measurement techniques; they work - more or less well - on all materials. One of the advantages of the calorimetry (heat conduction) that I work with is that it is not dependent on the properties of the samples (solid/liquid/gaseous, transparent/opaque, surface area etc). I have worked with calorimetry for about 20 years and I have never used the equations that make up 95% of this page. I may come back and try to do something here when I have time, but I do not know where to start... . — Preceding unsigned comment added by Larswa ( talk • contribs) 13:23, 2 March 2014 (UTC)
I undid this good faith edit. It was too specialized for the place where it went in the lead. Besides constant pressure calorimetry, there are also forms of calorimetry with constant volume, and with constant temperature. Chjoaygame ( talk) 18:11, 21 October 2015 (UTC)
I think a section about nuclear calorimetry is a very useful addition to article. This proposal is made given the aspects analyzed on talk:standard enthalpy of formation and talk:Hess's law especially about the heat of neutron capture reactions and its consequences on applying Hess law in calculating the heat of formation of isotopes like deuterium D(2) which seems to generate inconsistencies between various (standard thermochemical) assumptions like D2 heat of formation beeing considered zero by NIST tables.-- 5.2.200.163 ( talk) 10:15, 22 October 2015 (UTC)
My opinion is that nothing should be inserted on nuclear calorimetry unless sources are given. Much of the above discussion is based on 5.2.200.163's opinion of what seems reasonable, but both Chjoaygame and I have presented objections to his/her reasoning, and Wikipedia policy is not to include disputed material without sources. I do not think it necessary to repeat the whole argument again. Dirac66 ( talk) 18:02, 31 October 2015 (UTC)
Editor Chjoaygame has objected above to the sentence It [Hess's law] applies to the special case of paths consisting of chemical reactions (or changes of state) at constant temperature and pressure. I think this is just a case of sloppy wording. Chjoaygame has interpreted It applies ... as It must be at constant T and p, which I agree would be incorrect here. But I think what was meant is It is usually applied to, which just means that most applications of Hess's law consider the case of constant T and p for convenience, and does not imply that the law is invalid for other cases. I will change the wording of that article accordingly. Dirac66 ( talk) 18:02, 31 October 2015 (UTC)
I think the new section of the present article is OK now. I am not sure what you mean by the heat-or-reaction task. If you mean the Hess's law article which we were discussing above, I have just added a sentence linking it to the present article, so that readers of Hess's law can find the experimental details here. Dirac66 ( talk) 02:00, 2 November 2015 (UTC)
I don't Wikipedia's guidelines for which pages can get pronunciation guides is, but if this one applies, it should probably get one. When I was researching this topic, I first thought it was pronounced /kəˈlor.ɪ.mɛt.ri/, and asked some other people, who had not heard the term before. I looked to the wikipedia page, but it had nothing, so I had to use something like howtopronounce.com, but those kinds of sources never have IPA for whatever reason. I eventually found out that the correct pronunciation is something like /kæ.ləˈrɪm.ə.tri/ . It would be helpful if this was in the beginning of the article.
A few month ago, i created the article Richmann's law, which was the first equation for calorimetric calculations and should therefore be mentioned here. My english is to bad, to write in a proper scientific language. Maybe someone else can implement it and double check the new article. Thank you and greetings from german wikipedia. LukeTriton ( talk) 06:13, 31 January 2023 (UTC)