64. Solving a chemistry problem

6). Using the Calibration Graph Method in Elemental Quantitative Analysis in Photometry.
Based on the data given in table. 22, determine the content of the given elements in the investigated waste or natural waters using the calibration curve method.
Compare the result obtained with the MPC data and draw a conclusion about the possibility of returning the used waters to production or the suitability of natural waters for food purposes.
The variant number corresponds to the last digit of the student´s cipher.

Optical density, A Concentrations
N Defined element Determination method Volume of standard solutions Test solution, Ax Standard solution, μg/ml Test solution
1 ml 2 ml 3 ml 4 ml 5 ml
1 2 3 4 5 6 7 8 9 10 11
1 Fe
(MAC
=0.5
mg/l) With sulfo-salicylic
acid 0.09 0.178 0.286 0.356 0.445 0.244 79.3 Fe(%) in waste water from a 10 ml aliquot without pre-evaporation