Water from jordan lake was analyzed for its fe3+ content. A 20. 0-ml sample of lake water was acidified with nitric acid and treated with excess kscn to form a red complex (kscn itself is colorless). The solution was then diluted to 50. 0-ml and put in a 1. 00 cm pathlength cell, where it yielded an absorbance of 0. 345. For comparison, a 5. 0-ml reference sample of 4. 80 x 10-4 m fe3+ was treated with hno3 and kscn and diluted to 50. 0 ml. The reference solution was also placed in a 1. 00-cm cell and gave an absorbance of 0. 512. What is the concentration of fe3+ in jordan lake?.