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141. Solving a chemistry problem

141. Solving a chemistry problem

Seller: Derkach

Price: 1.20 USD

Available. The final price depends on the selected options and is checked before payment.

Product description

  • To determine lead in zinc ore by the addition method, a sample of ore weighing m g was dissolved in a mixture of acids, iron (III) was reduced, gelatin was added, and the solution was diluted to 200.0 ml. An aliquot with a volume of 20.00 ml was placed in an electrolyzer and the height h1 of the polarographic wave was measured at E = –0.45 B (NCE). Under these conditions, ions of copper, zinc, cadmium do not interfere with the determination of lead. After adding a standard VCT solution ml of 0.0020 M Pb (NO3)2 to the electrolyzer machine, the wave height h2 was obtained.

Calculate the mass fraction (%) of lead in the ore for the following options:

Option 1

m, g 1,000

h1, mm 22,0

Vst, ml 10,00

h2, mm 42,0

Additional information

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