Five standard chromium(VI) solutions were prepared through serial dilution technique with corresponding absorbance readings at 540 nm wavelength as follows:
A1=0.650 C1=1.9 ppm
A2=0.712 C2=4.0 ppm
A3=1.370 C3=6.0 ppm
A4=2.050 C4=8.0 ppm
A5=3.423 C5=10.0 ppm
The sample solution gives an average absorbance reading of 0.713. What is then the concentration of chromium (VI) ion in the sample?
Concentration of chromium (VI) ion=2.67