Lovibond Tintometer MD 100 Manual De Instrucciones página 48

Chemical Method
TPTZ
Appendix
Interferences
Removeable Interferences
1. PH interference: A sample pH after the addition of reagent, which is less than 3 or
greater than 4, may inhibit colour formation since the developed colour fades too
quickly, or can result in turbidity. This means that the pH value must be adjusted to
between 3 and 5 in the measuring glass before the addition of the reagent:
A suitable amount of iron-free acid or base, such as 1 N Sulphuric acid or 1 N
Sodium hydroxide, can be added on a drop by drop basis.
A volume correction must be carried out if significant volumes of acid or base are
added.
Bibliography
G. Frederic Smith Chemical Co., The Iron Reagents, 3rd ed. (1980)
EN Method Reference Book 1.0
Iron in Mo PP (224) / M224
EN
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