[curiouscat]

A patent I was reading had the following quote:

"It's basicity advantageously ranges from 40% to 60% and more particularly from 45% to 56%"

How is basicity expressed as a percentage? Maybe I am not seeing the obvious.

PS. In case it matters the material he refers to is a "Basic Aluminium Chlorosulfate" proposed as a novel flocculant.

[Tanvir242]

I found this in an article,
"Basic chromium sulfate (BCS) is one the main tanning chemical produced by chrome-chemical sectors of world. It is mainly a mixture of chrome-sulfate [Cr(OH)SO4] and sodium sulfate [Na2(SO4)], a green colored powder (Basaran et al., 2008) containing chromium tri-oxide [Cr2O3] (26%) and Na2(SO4) < 26% with basicity of 33%. This means that the chemical is one-third basic with respect to basicity of chromium hydroxide [Cr(OH)3]"
- ref  http://dx.doi.org/10.1016/j.jclepro.2015.05.123