please help thank you QUESTIONS Indicate how each of the following would affect
ID: 574427 • Letter: P
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please help thank you
QUESTIONS Indicate how each of the following would affect the value of the absorbance (too low, too high, no effect) of the indicated solution. Explain your answers a. A student prepares solution A using a 100.00 mL volumetric flask that is 1. initially wet. b. A student rinses the 10.00 mL pipet only with DI water in the preparation of D (but does the rest of the procedure as instructed). A student fills the volumetric flask containing solution B so that the bottom of the meniscus is above the mark on the flask (but does the rest of the procedure as instructed). c.Explanation / Answer
a) As the volumetric flask is already wet, so, on adding the solution A in it, will change the concentration of the solution. A little amount of water will affect its absorbance. It will be more dilute. So, absorbance will be lower than the actual value.
b) If the student rinses the 10.00 ml pipet only with DI water in the preparation of the sample, again the water in the pipet will get added up to the final volume and the solution will become diluted. Thus absorbance will be again lower than the actual value.
c) The student fills the volumetric flask containing solution B above the mark on the flask and directly measures the absorbance, it will not be affected. But if there are further additions to the procedure, then the absorbance will be affected. It depends on the further procedure.
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