[RASMB] sednterp values

John Philo jphilo at mailway.com
Wed Dec 6 10:24:16 PST 2006


Judith and all,

Tom is right that for some compounds one of the lowest regions of accuracy
for the polynomial functions is near zero concentration, but in this case
the errors are much too large. The database says the maximum error for that
compound is supposed to be 0.002 cp, so I suspect there is an error in the
coefficients in the database for that compound. 

I will check up on this when I can get to it and let everyone know what I
find. In the meantime I suggest doing a manual interpolation from the CRC
Handbook.

John

-----Original Message-----
From: rasmb-bounces at rasmb.bbri.org [mailto:rasmb-bounces at rasmb.bbri.org] On
Behalf Of Judith Kornblatt
Sent: Wednesday, December 06, 2006 8:50 AM
To: rasmb at server1.bbri.org
Subject: [RASMB] sednterp values


I recently tried to compute viscosity values for solutions of MnSO4 and 
MgSO4, using SEDNTERP, version 1.09. The smaller the concentration of 
the salt, the greater the effect on the viscosity! For example, at 20 C, 
(all values are X E-2)
    MnSO4, 50 mM    visc = 1.0308
                   10 mM              .988
                      1 mM              .967
                    0.1 mM              .9603

    MgSO4, 50 mM   visc = 1.0315
                   10 mM             1.035
                     1 mM              1.0576
                      0.1 mM           1.0678
            
This makes no sense to me, so I assume there is a problem somewhere. Has 
anyone else seen this sort of behavior? Any explanation?  

Judith Kornblatt 
Concordia University
Montreal, Quebec                

_______________________________________________
RASMB mailing list
RASMB at rasmb.bbri.org http://rasmb.bbri.org/mailman/listinfo/rasmb





More information about the RASMB mailing list