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Chemistry in your cupboard: Calgon


Calgon is a water softener, designed to remove dissolved minerals which reduce the efficiency of cleaning processes. This tutorial discusses the origin of these minerals in water and methods of removing them in terms of Group 2 chemistry, equilibria, and polymers.


This resource has been provided by, or developed in partnership with, Reckitt Benckiser

A tutorial covering: group 2 elements, acids and bases, polymerisation


Quiz questions (and answers), animations and 3D molecular graphics help illustrate the use of citrates to neutralise hard water. There is an accompanying practical which looks at testing water hardness by titration with EDTA.