Q = What is the concentration (assay) of this? The SDS states 90-100% but the catalogue states 88%
A = The 90 - 100% on the SDS covers the likely rage which this could be. The 88% in the catalogue is a nominal percentage value i.e. it is representative of a typical value. Each batch does vary in concentration and if required, the supplier should be able to verify this.
The 90% assay works out at works out 12.08M. The 88% assay works out at 11.81M
Q = What is the molarity of the concentrated solution?
A = Density = 1.209g/ml (1209g/L); Assay = 88%; MW = 90.08
Molarity = (density (g/l) x (assay%/100)) ÷ mol wt
Therefore: (1209 x 0.88) ÷ 90.08 = 11.81M