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Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

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At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

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How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

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Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax? A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual …

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• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn th…

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Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…


541 unknowns listed

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Wikenigma - an Encyclopaedia of Unknowns Wikenigma - an Encyclopaedia of the Unknown Science

'On Water' reactions

On water reactions are a group of organic reactions that take place as an emulsion in water and that exhibit an unusual reaction rate acceleration compared to the same reaction in an organic solvent, or compared to the corresponding dry media reaction. Source Wikipedia

“The notion of the special nature of water as a solvent for organic reactions began with examples of Diels–Alder reactions more than fifty years ago. The first quantitative data were reported by Rideout and Breslow, who showed that Diels–Alder reactions between nonpolar compounds proceeded at much higher rates in water (dilute homogeneous solution) than in organic solvents. Rate accelerations as high as 200-fold were noted in certain cases.”

“On Water”: Unique Reactivity of Organic Compounds in Aqueous SuspensionAngewandte Chemie, Volume 44, Issue 21 May 20, 2005

There is a growing list of organic chemical reactions which have been shown to have considerable acceleration 'on water'. It's speculated that the unique properties of molecules at the macroscopic phase boundary between water and insoluble hydrophobic oils might play a role - but these effects are yet to have a formally accepted explanation.


Also see: Water clustersplugin-autotooltip__plain plugin-autotooltip_bigWater clusters

Water has a long list of 'anomalous' physical (and chemical) properties (list here). Most are now fairly well understood - but there is currently no overall model to explain all of its unusual properties.

One anomaly is the existence and prevalence of s…


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