Lovibond Tintometer MD 100 Manual De Instrucciones página 74

Chemical Method
Thymol Blue
Appendix
Interferences
Persistant Interferences
1. pH values below 8.0 and above 9.6 can produce results inside the measuring range.
A plausibility test (pH-meter) is recommended.
Removeable Interferences
Salt error Correction of test results (average values) for samples with salt contents of:
Indicator Salt content per sample
Thymolblue 1 molar -0.22
The values of Parson and Douglas (1926) are based on the use of Clark and Lubs
buffers. 1 Mol NaCl = 58.4 g/l = 5.8 %
Bibliography
Colorimetric Chemical Analytical Methods, 9th Edition, London
EN Method Reference Book 1.0
pH-value HR T / M332
2 molars -0.29 3 molars -0.34
EN
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