Talk:PH

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I identified several areas for improvement that I believe will improve the readability, accessibility, and comprehensiveness of the article. Firstly, to update the page on its application, I will increase the number of real-world examples in the article to help readers understand the practical applications of pH in various fields. This will make the content more engaging and accessible to readers who do not have a background in chemistry or science. I'll add clear subheadings to make the article easier to navigate and understand. This will help readers find the information they need faster while also making the content more organized. Finally, in order to improve the clarity of the images, I'll go over the images in the article and revise their captions to provide more detail and context for the reader. I'll also look for ways to include more diverse images that show how pH can be used in real-world situations. Veggietaquito (talk) 04:15, 12 March 2023 (UTC)Reply

For chemists, comprehensiveness of the chemical parts of the article is very high. But for non-chemical audience adding the  examples of practical application  for "real-world" cases may be useful for the improvement of readability  . ChemEdit (talk) 13:44, 20 March 2023 (UTC)Reply

How to make a difference between a solid ang gas 222.127.94.221 (talk) 13:34, 19 May 2025 (UTC)Reply

You cannot log something with a unit/dimension. You either log the absolute value, or you log the concentration/activity divided by some reference concentration/activity. Compare dB (decibel). The reason is that log can be substituted by its MacLaurin series and otherwise you would end up with a sum of dimensionless + unit + unit squared + unit cubed and so on. 83.223.9.100 (talk) 08:43, 27 April 2023 (UTC)Reply

I'm mildly surprised to see " An alternative method of measuring pH is using an electronic pH meter" as if this is not the standard and people who work with water chemistry as part of their job are out there staring at what color the water is, hoping to pase out the ph that way. This seems more like a something students in a lab would be doing as opposed to a day-to-day thing. Maybe I'm wrong, but in my line of work everyone uses an electronic meter. Beeblebrox (talk) 19:06, 4 October 2023 (UTC)Reply

At the very beginning of this, the "p" is said to be "potential", and this is internally linked to "electric potential". This is misleading (notwithstanding that later it is linked to an electric potential in an electrochemical cell in "hydrogen electrode"). The original "p" was short for the German word "Potenz", meaning "potency". "Potential" is OK in English, meaning the inherent ability to do something - low pH means likely to corrode, dissolve, etc. Bobgid (talk) 18:48, 30 March 2024 (UTC)Reply

For the p{H} subsection, wouldn't it be more appropriate to have the title "p_H." ? Since we are basing off this pH definition from Soresen and he defines it as such, not p[H]. Veggietaquito (talk) 17:29, 14 April 2023 (UTC)Reply

Only if you're very careful with your typography! A lower case p with a subscripted H looks awfully like a big P in front of a smaller H! Since "pH" is always printed like that, I think it more sensible to leave it as p[H], where the "p" is funtioning as a sort of mathematical operator: "minus log(10) of", and the [H] is what it's operating on. Also used frequently in pOH, pCl, p[acetate], etc. Bobgid (talk) 19:00, 30 March 2024 (UTC)Reply

pH ~= -log₁₀([H⁺]/M) and M = mol/L??? LMFAO! pH is what a pH meter (calibrated and suitable for the AQUEOUS SOLUTION the electrode (junction) is immersed in) measures. Defining it as (thermodynamic) activity is a rabbit-hole which is simply not practically helpful. (I know, been there, done that). pH meter can measure pH less than zero and more than 14 (been there, done that), but the more 'extreme' the pH, the less useful the metric is for predicting solution properties. The article on thermodynamic activity goes into more depth (along with the article on Chemical potential). Really, pretending that pH measures activity is mostly about sweeping the inconvenient details under the rug. (A crude way to understand that is to consider most solution activities are defined as ion concentration approaches zero; hardly useful in most physically realizable contexts.) The approximate "equation" given by the article is improper. It is wrong to divide a physical quantity by a unit of measurement (or in this case a ratio of two units of measurement - moles and liters). There is absolutely no reason not to require [H⁺] be expressed in units of mol/l. Full stop. There is perhaps a conceptual issue if it's then required to "remove" the units. So, sure divide it by 1 mol/l, even call that 1 M, but it's absolutely wrong to divide by (null quantity)M. Another minor issue is that it's well established that H⁺ as meant here should be designated as H⁺(aq) since it is NEVER the 'bare' proton that exists in (aq) solution and since the H₃O⁺ species is also unlikely to exist in there (see hydronium). (I note that the hydronium article uses the same incorrect pseudo-equation dividing a quantity by a unit of measure.) I'll also note that the sentence (from activity article):"In general, the activity depends on any factor that alters the chemical potential. Such factors may include: concentration, temperature, pressure, interactions between chemical species, electric fields, etc." also holds for pH and, I think, should be included in this article. It's also true that a) the solution may affect the semi-permeable electrode membrane and can distort the readings (provide inaccurate pH (or activity) and b) One thing most (esp. non-solid state) electrodes suffer from is cross-membrane potential drift - diffusion and polarization both are real problems when attempting to measure pH over time) so (frequent) calibration of the electrode is essential for accurate measurements.98.19.179.27 (talk) 04:14, 28 May 2025 (UTC)Reply

pH+pOH depends on both temperature and pressure. I am a little surprised that the temperature, presumably at 1.0000atm, can be measured that accurately. If it can, though, a WP:RS would be nice. Also, some of the pressure dependence. Gah4 (talk) 05:55, 26 July 2025 (UTC)Reply