Tintometer Lovibond MD 100 Manuel page 49

Chemical Method
Phenol Red
Appendix
Interferences
Removeable Interferences
1. Salt error Correction of test results (average values) for samples with salt contents
of:
2.
Salt content of the sample
30 g/L (seawater)
60 g/L
120 g/L
180 g/L
according to Kolthoff (1922)
1)
3. When testing chlorinated water the residual chlorine contents can influence the
colour reaction of the liquid reagent. This can be avoided by adding a small crystal
of Sodiumthiosulphate (Na
PHENOL RED solution.
Bibliography
Colorimetric Chemical Analytical Methods, 9th Edition, London
EN Method Reference Book 1.0
Correction
-0.15
-0.21
-0.26
-0.29
according to Parson and Douglas
2)
(1926)
S O ⋅5 H O) to the sample solution before adding the
2 2 3 2
pH value L / M331
1)
2)
2)
2)
EN
49