Spectrophotometric determination of lead with dithizone

Spectrophotometric determination of lead with dithizone General remarks 

In virtually neutral to alkaline solution with dithizone, lead (II) ions 

The PbDz2/CCl4 solution shows a distinct maximum at 520 nm. However, pure dithizone may also absorb at this point. An error may therefore arise if excess dithizone is incompletely eliminated. Over-thorough washing out of the dithizone, on the other hand, may lead to decomposition of the PbDz2 In order to minimize this source of error the lead dithizonate is treated 

Lead enters the hydrochloric aqueous phase and the HDz equivalent to the 

The method is suitable for the determination of lead ions in concentrations between 0.005 and 20 mg/1. 

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