Talk:Boyle's law

Constant temperature?

In the beginning of the article it is correctly stated that: "Boyle's law describes the inversely proportional relationship between the absolute pressure and volume of a gas, if the temperature is kept constant within a closed system."

So why does the illustration depict a candle flame ? If weights are added or removed, the volume should change. That is all that the illustration need show or should show. I am not able to alter the illustration, but I think the candle should be removed by someone who knows how. --Ben Best (talk) 00:08, 11 September 2010 (UTC)

I agree. It is odd to use what appears to be a piston surrounded by a water jacket (I'm assuming the "300" is degrees Kelvin). This is a very confusing graphic and should be removed. It is not even self-consistent, since it shows both a varying pressure and what appears to be a second piston (with a constant load) which would illustrate a constant pressure. The root cause of this error may be it is using a similar graphic for "Charles Law" (which correctly illustrates the constant pressure variable V-T relationship, but ommiting to remove the "constant pressure" piston graphic to the left (which is simply wrong here). Also it is highly unrealistic, since the assumption is heat is flowing through the walls of the piston, even though THERE IS NO TEMPERATURE DIFFERENTIAL as shown. The 300 degree temperature indicator should be pointed to the water jacket, not the gas (then there would be a temperature differential so heat can flow in and out). The candle is irrelevant, since 300K could be assumed to be room temperature. Or the water jacket should be replaced with an ice bath and the fixed temperature would be 0 degrees Centigrade. Boyles law should be applied to systems which have come to equilibrium, and not the rapidly changing dynamic model shown. Pmarshal (talk) 08:53, 1 February 2013 (UTC)

0 pressure?

What happens to an ideal gas in an infinite space when the pressure is 0? Does the gas expand to infinite volume? --Curtis95112 (talk) 01:22, 17 January 2008 (UTC)

Pressure will never be 0 in an infinite volume hypothetical scenario because you have introduced a gas. Regardless of how little you have added, there will always be that finite and measurable amount of gas in an infinte space. As volume increases, the pressure and temperature will decrease. Subsequently, you should expect the pressure to approach but never reach absolute 0, and you should expect the temperate to approach but never reach absolute 0. Gauzeandchess (talk) 04:21, 8 March 2012 (UTC)

Discovery

According to several sources, including Physical Chemistry by Laidler, Meiser, and Sanctuary, Boyle did not discover this relationship, but rather, was the first to publish it. It was discovered by Richard Towneley and Henry Power, two amateur scientists. Boyle confirmed their work and received the credit. As this appears to be the case in most scientific literature, I'm going to change this article accordingly. KraDakar 18:01, 15 July 2006 (UTC)

P vs. p

On all the other gas law pages, pressure is a capital P. On this one, it's a lowercase p. Everywhere else, I've seen an uppercase P. Perhaps this should be changed? 71.240.251.37 04:35, 13 December 2006 (UTC)

Agreed. Done. -- 64.9.237.36 00:41, 17 January 2007 (UTC)

WRONG. Capital P denotes POWER, not pressure. Uxorion 10:22, 13 August 2007 (UTC)

WRONG. Lower case p denotes MOMENTUM, not pressure. --Vaughan Pratt (talk) 00:21, 5 August 2008 (UTC)

Boyle was actually a english teacher at the time —Preceding unsigned comment added by 98.209.123.148 (talk) 02:25, 5 March 2009 (UTC)

Illustration requests

{{reqdiagram}}

• A graph to illustrate the mathematical relationship.
  •  Done? pfctdayelise (talk) 17:49, 26 July 2008 (UTC)
• An illustration to show the relationship using idealized hard spheres.

-- Beland 07:02, 7 April 2007 (UTC)

 Done pfctdayelise (talk) 19:02, 26 July 2008 (UTC)

Equation

this section seems to be incomplete, maybe due to a bad edit. Sorry folks but I'm new here so I still need some time to understand how to make proper modifications. Podi74 (talk) 12:22, 19 December 2007 (UTC)

Fixed, vandal deletion. Thanks, Vsmith (talk) 12:36, 19 December 2007 (UTC)

This article has digressed into jibberish

This article is now a (more or less) complete mess. Too much is indigestible, and notation is inconsistent. Useful stuff has been removed. Unimportant stuff has been added. It has deviated from the modern form. The English is terrible in places. Some interesting stuff has been added and perhaps should be kept, but for the most part it is time for a serious reversion- which I intend to do unless someone explains here why this version (1/1/08), or which portions of this article, should be kept. Key point- just because the orginal author/discover described something in a particular way, it does not mean that that is the current or pedagogically most useful way to present the material today. blackcloak (talk) 02:26, 2 January 2008 (UTC)

Indeed. The author seems to have taken 23 Enigma seriously and declared that there are 23 gas laws, without saying where this number comes from. Why not just merge the essential content of this article. into Ideal gas laws? This would be the historical bits and perhaps the nice little animation. --Vaughan Pratt (talk) 00:20, 5 August 2008 (UTC)

Practical application of Boyle's Law

It would be useful to add a real world application. One suggestion is barotruama, in which diver's lungs are injured by expanding air as they ascend to the surface, which reduces pressure, all the time in a relatively constant temperature. —Preceding unsigned comment added by Maxthedrive (talk • contribs) 23:47, 4 June 2008 (UTC)

the video on this page contains an error central to boyles law and should be removed/replaced. It states that as a vacuum is generated in the jar, the pressure is higher outside the balloon and lower inside the balloon, so the balloon expands. This is in fact the opposite of what is happening.

Another suggestion is Body plethysmography. There Boyle's law is used to determine for example the absolute lungvolume of the patiënt. Idea?

Gpsgek (talk) 12:06, 17 September 2008 (UTC)

Wow -what an embarrassing error - Boyle's law reflects ideal gasses, not real

By chance, I passed by and was perplexed with the statement -- "Boyle's law relates more effectively to real gases[3] due to its description of such gases consisting of large numbers of particles moving independently of each other.[3]" This is plain nonsense. What does it mean to "relate more effectively"? and the words following "due to" do not add any information value, at best it is a simplistic definition of any gas, at worst it is patent nonsense.

The lede states correctly that Boyle's law is related to the ideal gas law - in fact it is most easily derived from that law. It therefore applies to ideal gasses, only. The text was introduced by User:Uxorion in Revision of 13:19, 13 August 2007, so the text has been on the page for over a year(!). Uxorion seems to be a bona fide editor, so this is not a practical joke or a prank, as I initially suspected. The editor's last contribution was on 5 September 2007 - a year ago. Perhaps the editor was very tired at the time. I'm changing the wording. Power.corrupts (talk) 07:21, 25 September 2008 (UTC)

Adiabatic Heating

Boyle's law states that the pressure and volume are inversely proportional at a fixed temperature. But if you increase the pressure of a gas will it not heat adiabatically? I assume that under experimental conditions the gas is allowed to cool to the temperature prior to compression. Would it be correct to say that when adiabatic heating is accounted for, P and V are not inversely proportional? Does the ideal gas law account for this? Ratsbew (talk) 19:54, 20 November 2008 (UTC)

Well needed re-write

Looking at this article there are an incredible amount of factual errors regarding its origins. It also fails to cite any relevant sources, leading to mere unqualified speculation. As someone deeply involved in the field of 17th Century science and Boyle's texts (including the specific text that the law originates) I'd be willing to re-write it, but not for a while yet as I'm deeply involved in writing a thesis at the moment. TorstenGuise (talk) 16:09, 10 December 2009 (UTC)

Mariotte's law: Correction: 1676 → 1679

The article's "Discovery" section states that Edme Mariotte independently discovered Boyle's law of gases in 1676. This date, 1676, is cited in a number of sources, but it's wrong. The correct date is 1679.

The evidence for the 1679 date is:

• Mariotte's essay "De la nature de l'air" was reviewed by the French Royal Academy of Sciences in 1679. See: (Anon.) (1733) "Sur la nature de l'air," Histoire de l'Académie Royale des Sciences, 1 : 270-278. On the upper margin of each page, the date "1679" appears quite clearly.

• Mariotte's essay "De la nature de l'air" was also reviewed in the Journal des Sçavans (later: Journal des Savants) on 20 November 1679. See: (Anon.) (20 November 1679) "Essais de physique, … ," Journal des Sçavans, pp. 265-269.

• The Catholic Encyclopedia (1913) also states that Mariotte's essay "De la nature de l'air" was published in 1679. See: Catholic Encyclopedia (1913), vol. 9.

In neither the Histoire de l'Académie Royale des Sciences nor the Journal des Sçavans does the reviewer state that Mariotte had published anything on the subject previously. Indeed, I reviewed the accounts of both journals for the year 1676 and I found nothing in either mentioning any research by Mariotte on the subject of air.

Additional, very strong evidence that Mariotte did not write his essay De la nature de l'air in 1676 is provided by two other sources:

• In September 1677, Mariotte wrote a letter to Gottfried Leibniz in which he discussed his experiments with air in mercury barometers. Here he does not mention his essay De la nature de l'air ; nevertheless, he does mention the relation between the volume of air in a mercury barometer and its pressure. From p. 219: After explaining that when air in the barometer tube doubles its volume, its pressure is halved, "On a trouvé le mesme en d'autres proportions, … " (One found the same in other proportions, … ). That is, the same relation between the pressure and the volume of the confined air holds proportionately for other initial volumes, and he then gives an example in which, when the confined air expands four-fold, its pressure drops to a quarter of its initial value. This is Boyle's / Mariotte's law. See: Heinz-Jürgen Hess, ed., Gottfried Wilhelm Leibniz: Sämtliche Schriften und Briefe. Dritte Reihe : Mathematischer Naturwissenschaftlicher und Technischer Briefwechsel, Zweiter Band : 1676-1679 [Gottfried Wilhelm Leibniz: Collected Writings and Letters. Third series: Mathematical, scientific and technical correspondence, 2nd volume: 1676-1679] (Berlin, D.D.R.: Akademie Verlag Berlin, 1987), pp. 218-220.

• In 1678, Mariotte published his Essai de Logique. On pages 183-194, he poses (p. 184) and solves the problem of determining how much air must be introduced into a mercury barometer in order to reduce the height of the mercury in the barometer by a given amount. Again, nowhere does he mention his essai De la nature de l'air as he solves this problem — even though he again presents Boyle's / Mariotte's law. From p. 191: " … on conclura le verité de ce principe d'experience; sçavoir que l'air se condense à proportion des poids dont il est chargé, … " ( … one will conclude the truth of this experimental principle; to know that air is condensed in proportion to the weight with which it is loaded … ). See: Edme Mariotte, Essai de Logique … (Paris, France: Estienne Michallet, 1678).

I did some more investigating regarding the year in which "De la nature de l'air" was published:

• The Biographie Universelle (1820) gives the date of Mariotte's "De la nature de l'air" as 1679. See: Joseph Fr. Michaud and ‎Louis Gabriel Michaud, ed.s, Biographie Universelle … vol. 27, (Paris, France: L. G. Michaud, 1820), p. 174. From p. 174: "Son Discours sur l'air, qui parut en 1679, renferme une suite d'expériences intéressantes, alor absolument neuves." (His Discourse on air, which appeared in 1679, contained a series of interesting experiments, at that time absolutely new.)
• However, the Nouvelle biographie universelle (1860) gives the date of Mariotte's "De la nature de l'air" as 1676. See: Hoefer, ed., Nouvelle biographie universelle … vol. 23, (Paris, France: Didot Frères, Fils et Cie., 1860), p. 800.

It is the date of 1676 that was listed in the Nouvelle biographie universelle (1860) which seems to have been the source of the error. See, for example:

• Footnote on p. 76 of: George F. Rodwell (August 13, 1864) "On the supposed nature of air prior to the discovery of oxygen [continued]," The Chemical News, 10 (245) : 74-77.
• Footnote on p. iv of the Preface in: P. G. Tait, Sketch of thermodynamics (Edinburgh, Scotland: Edmonston and Douglas, 1868).
  

VexorAbVikipædia (talk) 01:34, 14 June 2015 (UTC)

Boyle's law and the human breathing system

Hi, I added this section due to Boyle's law often being used in an explanation of breathing. Let me know if you have any advice, questions, objections etc. RickyBennison (talk) 12:59, 8 November 2016 (UTC)

What is the name of the constant k in the eq. PV=k?

I think the name should be Boyle constant.... Akashdip Neogi (talk) 15:20, 6 October 2017 (UTC)

Dimensions of the constant k in PV = k

Like Newton's gravitational constant, k here is not dimensionless.

Dimensions:

P is force per unit area, i.e. M/L/T-2 * L/-3 and thus M/L-2/T-2 V is L3 Thus PV is M/L/T-2, the dimensions of force.

This is entirely proper (for nothing is properer than Newton), but maybe the article should mention this, and say that consistency is required.

For example: P in newtons per square metre, V in cubic metres, PV yields a force in newtons. Or: P in pounds force per square foot, V in cubic feet, PV yields pounds force.

John Wheater (talk) 09:08, 11 March 2021 (UTC)

Animation misleading

The animation shown should be linear, rather than curved, as the relationship is directly proportional.

Came here to say the same thing and then realized that the figure is correct. A straight line is expected when two quantities are 'directly proportional', but the curved line is expected when they are 'inversely proportional'. Example: if P = 1 and V = 1 and then you increase the pressure by a factor of 5 (P = 5), the volume decreases by a factor of 5 (V = 0.2); moving an equivalent amount on the X-axis to P = 10 leads to only a marginal decrease on the Y-axis to V = 0.1. Dorstlesser (talk) 7/7/2021

What does this mean in a vacuum

I’ve always heard that space is a vacuum so I guess I’m wondering is this our great hope for a space faring civilization 😩🙏 2600:387:F:D14:0:0:0:8 (talk) 18:37, 27 March 2022 (UTC)

Verification of Boyle's law

Relationship between volume and pressure of an enclosed gas — Preceding unsigned comment added by 196.207.37.208 (talk) 19:02, 11 September 2022 (UTC)

Boyle Heights

How did Boyle figure all this out?? 41.115.39.64 (talk) 07:51, 13 December 2022 (UTC)

History, para 2, sentence 1 says "had published it in."

Citation 6 says 1662, I am new at editing, have tried the sandbox but can't get it to work, and I don't know how to add citation 6 or change 9 to 6.... but I am going to change this sentence to " had published it in 1662" but the citation will need to be changed. Sudzydoogiedawg (talk) 10:43, 29 December 2022 (UTC)