A viscometer was used to measure power law parameters K and n for aqueous solutions of (carboxymethyl) cellulose (CMC),taken from a bubble column. The results were analyzed by plotting n as a function of Log K. Literature data and the present experiments show that dilution gives a slope of -0.147 on the Log K-n plot. Results with different molecular weights show, by contrast, a slope of -0.345. Results from the bubble column are consistent with (i) change of CMC molecular weight due to shear, the slope of the Log K-n plot being -0.345, and (ii) change of CMC molecular weight due to oxidation by hydrogen peroxide when this was added : the slope of the Log K-n plot was -0.223. That this was less than -0.345 is believed to be due to dilution. The effect of moderate temperature changes was also summarized. An important conclusion is that when CMC solutions are used in bubble columns or stirred tanks for mass or heat transfer studies, attention must be given to changes of properties due to shear, oxidation, dilution, and temperature.