Please register and log-in to create and edit pages

User Tools

    Please register and log-in to create and edit pages

Site Tools


Main Menu

Main menu
Click categories to expand


A-Z listingplugin-autotooltip__plain plugin-autotooltip_bigA-Z listing

This is an alphabetical index of all content pages.


Other categories

Utilities

Contacts
Register

Also see

Importance Ratings
News
Legal
Donate/Sponsor


Wikenigma supports:


Feeds etc
rss / xml feed
sitemap file
A-Z listing (archived)

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

Liesegang rings

Liesegang patterning is a special type of chemical pattern formation in which the spatial order is formed by density fluctuations of a weakly soluble salt. From analytical chemistry we know many different reactants that form a precipitate (sparingly soluble salt) when they react with each other. A good example for this behavior is the reaction of silver-nitrate (AgNO3) and potassium-dichromate (K2Cr2O7).
If one of these components is evenly distributed in a swollen gel (e.g. in gelatine), and the solution of the other diffuses into it, the spatial distribution of the slowly forming precipitate will not be continuous. A series of precipitate zones (bands or rings depending on the geometry of the experimental setup) will form according to some simple scaling laws.
Source: In Silico

The rings were first described in 1855 by the German chemist Friedlieb Ferdinand Runge, who was experimenting with silver-nitrate (AgNO3) and potassium-dichromate (K2Cr2O7).

Over the last century and a half, many (competing) theories have been put forward to explain the phenomenon - including the 'supersaturation' theory, the 'adsorption' theory, the 'coagulation' theory etc etc. See Wikipedia


    Share this page :

X

Dear reader : Do you have any suggestions for the site's content?

Ideas for new topics, and suggested additions / corrections for old ones, are always welcome.

If you have skills or interests in a particular field, and have suggestions for Wikenigma, get in touch !


Or, if you'd like to become a regular contributor . . . request a login password. Registered users can edit the entire content of the site, and also create new pages.

( The 'Notes for contributors' section in the main menu has further information and guidelines etc.)

Show another (random) page

DOKUWIKI IMPLEMENTATION DESIGN BY UNIV.ORG.UK JULY 2021