Question

The spectrophotometer must be calibrated during the experiment. For calibration, the "blank" standard solution will be used. What is the Cu2+ concentration of the "blank" solution?

A) 0 g/L
B) 0.1 g/L
C) 1 g/L
D) 10 g/L

Answer 1

The "blank" solution used to calibrate a spectrophotometer has a Cu2+ concentration of 0 g/L, which is used to set the device's baseline to ensure accurate spectrophotometric analysis.

Step-by-step explanation:

The concentration of Cu2+ in the "blank" solution used to calibrate a spectrophotometer is intended to be zero, as the blank is used to set the baseline for the instrument. Therefore, the correct answer for the Cu2+ concentration of the "blank" solution is A) 0 g/L.

The purpose of the blank is to correct for any absorbance due to the solvent and the cuvette itself. By setting the spectrophotometer with a blank, you ensure that subsequent measurements of actual samples reflect just the absorbance due to the substance of interest, in this case, Cu2+.

It is essential for accurate spectrophotometric analysis and obtaining a correct molarity of sample solutions.