Reference no: EM132590977

Co and Ni can be analysed simultaneously by their reaction with 2, 3-quinoxalinedithiol. Molar absorptivity data at the wavelengths are:

Molar Absorptivity.ε

510 nm

656 nm

Co-Complex

36400

1240

Ni-Complex

5520

17500

A 0.519 g sample was dissolved and diluted to 50 ml. A 25 ml aliquot was treated to eliminate interferences; after addition of 2, 3-quinoxalinedithiol, the volume was adjusted to 50 ml. this solution had an absorbance of 0.477 at 510 nm and 0.219 at 656 nm in 1.00 cm cell. 

Calculate the parts per million of Co and Ni in the sample.