Phenolphthalein and User talk:Susvolans: Difference between pages

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[[Image:Phenophthalein.png|frame|right|Illustration of bond structure of phenolphthalein]]

== Archives ==

[[Image:Titration.png|frame|left|Rough illustration of a titration with phenol­phthalein prior to the [[endpoint]]]]

[[User talk:Susvolans/Archive 1|August 2004 to September 2005]]

== Thank you ==

'''Phenolphthalein''' is a sensitive [[pH]] [[pH indicator|indicator]] with the formula C₂₀H₁₄O₄. Often used in [[titration]]s, it turns from colorless in [[acid]]ic solutions to pink in [[base (chemistry)|basic]] solutions, the color change occurring between pH 8 and pH 10. If the concentration of indicator is particularly strong, it can appear purple.

Thank you for speaking up on the behalf of a user you did not even know. I appreciate your efforts for justice. Should you have any lingering concerns, I encourage you to come to my talk page and join the dialog there on what has occured. Discussion is the best way to calm stormy waters. [[User:TheChief|<font color=#0000ff>The</font><font color=#ff7f00>Chief</font>]] [[User_talk:TheChief|(<font color=#0000ff>Pow</font><font color=#ff7f00>Wow</font>)]] 17:30, 3 November 2005 (UTC)

In strongly basic solutions, phenolphthalein's pink color undergoes a rather slow fading reaction and becomes colorless again. In other words, the molecule has three forms:

==Ignore all rules==

<table style="margin-left:auto; margin-right:auto;">

First, obviously, if rule 5 were deleted, it would become four pillars rather than five. I think that any change to the four/five pillars should be well discussed on its talk page first. Failure to do so would be to ignore all rules, which could be seen as [[WP:POINT]].

<tr>

<td align="center">H₂Phenolphthalein <br> acidic <br> no color

<td align="center">&harr;

<td align="center"> Phenolphthalein^2- <br> basic <br> pink

<td align="center"> &harr;

<td align="center"> Phenolphthalein(OH)^3- <br> strong alkaline <br> no color

</table>

I personally think that the five pillars document is fine, because it says that there are no rules other than those listed, and the writers' rules of engagement are one of the pillars. The real problem is that Ignore All Rules is the wrong summary of the guideline, and is sufficiently wrong as to be a destructive title, because it can easily be read as meaning that one can ignore civility. [[User:Robert McClenon|Robert McClenon]] 18:16, 3 November 2005 (UTC)

The fading reaction is sometimes used in undergraduate classes for the study of reaction kinetics.<br>

Thanks Susvolans - I'm just taking baby steps for now [[User:Redkaty|Redkaty]] 14:38, 10 November 2005 (UTC)

Phenolphthalein is insoluble in [[water]], and is usually dissolved in [[alcohol]]s for use in [[experiment]]s. It is itself a weak acid, which can lose H⁺ ions in solution. The phenolphthalein molecule is colorless. However, the phenolphthalein ion is pink. When a base is added to the phenolphthalein, the atom &harr; ions equilibrium shifts to the ionization because H⁺ ions are removed, (by [[Le Chatelier's principle]]).<br>

==Final decision==

&nbsp;<br>

The arbitration committee has reached a final decision in the [[Wikipedia:Requests for arbitration/Louis Epstein]] case [[User:Raul654|&rarr;Raul654]] 02:12, 12 November 2005 (UTC)

== [[Wikipedia:Neutral point of view]] ==

Phenolphthalein has been used for over a century as a [[laxative]], but is now being removed from the market because of concerns over [[carcinogen]]ity. However, the small amounts usually used in experiments are harmless. Phenolphthalein is also commonly used in a mixture, primarily by forensic scientists, to test for the presence of blood.

Regarding the [http://en.wikipedia.org/w/index.php?title=Wikipedia:Neutral_point_of_view&curid=39805&diff=28415528&oldid=28413773 revert; the claim that all five pillars are unchangeable has no foundation in policy], why is it there then? Is the [[Wikipedia:Five pillars]], wrong? -- [[User:Zondor|Zondor]] 17:42, 15 November 2005 (UTC)

== Updated poll ==

Phenolphthalein is used to perform a presumptive blood test, and is commonly known as the [[Kastle-Meyer test]]. A dry sample is collected with a swab or filter paper. First a few drops of alcohol, then a few drops of phenolphthalein and finally a few drops of hydrogen peroxide are dripped onto the sample. If the sample turns pink then it is a positive test. This test is nondestructive to the sample, it can be kept and used in further tests at the lab. This test has the same reaction with human blood and animal blood so further testing would be required to determine which it is.

I have completely changed the poll. Please see [[Wikipedia talk:Naming conventions (years in titles)/Poll]] --[[User:AllyUnion|AllyUnion]] [[User talk:AllyUnion|(talk)]] 02:39, 17 November 2005 (UTC)

==External links==

*[http://www.chemguide.co.uk/physical/acidbaseeqia/indicators.html Page on different titration indicators, including phenolphthalein]

*http://wwwsoc.nii.ac.jp/jsac/analsci/pdfs/a15_0611.pdf

== curly quotes ==

[[Category: pH indicators]]

May I ask why you moved [["—All You Zombies—"]] to [[“—All You Zombies—”]]? &mdash; [[User:Flamingspinach|flamingspinach]] | [[User_talk:Flamingspinach|(talk)]] 06:13, 21 November 2005 (UTC)

[[da:Phenolphthalein]]

[[de:Phenolphthalein]]

== class="wikitable" ==

[[es:Fenolftaleína]]

[[nl:Fenolftaleïne]]

I wouldn't know how, but why would you want to anyway? [[User:Bluemoose|Martin]] 14:32, 22 November 2005 (UTC)

[[ja:フェノールフタレイン]]

:Aha, so you mean find occurances where it was expanded when it used [http://en.wikipedia.org/w/index.php?title=Template:Prettytable&oldid=23029079 this] revision of the prettytable. In which case the only way I think you could find them would be to get someone to use an SQL query on the database dump, but I don't know how successful that would be. At the moment I am not capable of doing this, but plently of other people are. [[User:Bluemoose|Martin]] 16:10, 22 November 2005 (UTC)

[[pt:Fenolftaleína]]

[[sv:Fenolftalein]]