Answer:
the change in absorbance reflects the reaction rate. As the reaction completes, its rate slows, so the absorbance levels off.
Step-by-step explanation:
A spectrophotometer measures the amount of light of a particular color passing through the sample. The changing color of the dye will change the value read by the spectrophotometer..
Apparently, the absorbance increased as the reaction progressed. When the reaction was almost complete, the absorbance increase slowed or stopped.