80. Solving a chemistry problem

10. V ml of waste water was placed into two volumetric flasks with a capacity of 100 ml. 10 ml of CuSO4 standard solution (T(Cu) = 0.001000) was added to one flask. Ammonia solutions were introduced into both flasks. Rubeanic acid and diluted to the mark with water. When photometry solutions received optical densities Ax and Ax st.
Determine the concentration (g/l) of copper in wastewater for the following options:
1) V, ml = 10; Ax = 0.240; Ah st \u003d 0.380
2) V, ml = 20; Ah = 0.280; Ah st \u003d 0.420
3) V, ml = 30; Ax = 0.320; Ah st \u003d 0.460
4) V, ml = 40; Ah = 0.400; Ah st \u003d 0.540
Answer: 1) 1.71 g / l; 2) 1.00 g/l; 3) 0.76 g/l; 4) 0.71 g/l.