The measured value of the absorbance will be lower than the actual
Since the sample solution was added to a cuvette that contained a
small amount of water, the solution was diluted and its concentration
decreased. According to Beer's law, absorbance varies directly with
concentration, so when the concentration of the sample decreased, the
absorbance of the sample also decreased. The cuvette should have been
rinsed with the sample solution
before it was filled.
In addition, the water on the outside of the cuvette could cause
inaccurate measurements or damage the instrument. The water on the
outside should be removed with a lab tissue.
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