How do you measure the 5 mL of 2 M nitric acid which is added to the 100 mL volumetric flask in step 3?

The concentration of Fe³⁺ in the stock haematite solution is large and if it were mixed with KSCN the light absorbance would be too large to accurately measure. How is this problem avoided in the method for this experiment?

10.0 mL of a solution of Fe³⁺ was placed in a 100 mL volumetric flask. 5mL of nitric acid and 5 mL of KSCN solution were added. Water was added to make the solution up to the mark on the neck of the volumetric flask, and the solution was thoroughly mixed. The concentration of the solution in the volumetric flask was determined to be 0.00222 mol/L by spectrophotometry. What was the concentration of the original Fe³⁺ solution?

The graph below is a calibration curve for determining the concentration of Cu²⁺ from light absorbance at a wavelength of 610 nm. This calibration curve was created in the same way as the one involving Fe²⁺ you will generate in this experiment.

If solution of copper has an absorbance of 0.901 at 610 nm, what was the concentration Cu²⁺ in the solution?

The part shown in the figure below is to be used as a rotating member in a machine. Which of the following will NOT increase the fatigue life of this part?

The part shown in the figure below is to be used as a rotating member in a machine. Which of the following will NOT increase the fatigue life of this part?

The part shown in the figure below is to be used as a rotating member in a machine. Which of the following will NOT increase the fatigue life of this part?