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This thread http://www.natscience.com/Uwe/Forum.aspx/chem/2180/Origin-of-the-SI-Unit-Katal at natscience.com has some pointers as regards the etymology of "katal". 212.84.103.144 ( talk) 04:25, 27 June 2010 (UTC) reply

The katal is invariant of the measurement procedure, but the numerical quantity value is not and depends on the experimental conditions. Therefore, in order to define the quantity of a catalyst, the rate of conversion of a defined chemical reaction is specified as mols reacted per second.

What is meant here? Rewrite? 178.38.108.161 ( talk) 17:09, 12 January 2015 (UTC) reply