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At a pH of 8.5 – 9.5 zinc ions react with zincon to form a blue colour complex. Acidic, alkaline and buffered samples have to be adjusted to pH 9 for the test.

Zinc is one of the most often used metals for surface finishing. Its content in waste water from e. g. electroplating companies has to be monitored regularly.

At a pH of 8.5 – 9.5 zinc ions react with zincon to form a blue colour complex. Acidic, alkaline and buffered samples have to be adjusted to pH 9 for the test.

Zinc is one of the most often used metals for surface finishing. Its content in waste water from e. g. electroplating companies has to be monitored regularly.

At a pH of 8.5 – 9.5 zinc ions react with zincon to form a blue colour complex. Acidic, alkaline and buffered samples have to be adjusted to pH 9 for the test.

Zinc is one of the most often used metals for surface finishing. Its content in waste water from e. g. electroplating companies has to be monitored regularly.