Pre-lab 8.4 Questions See Procedure 8.4 and Table

5 Based on the precision of an analytical balance and volumetric glassware, what is the precision of the calculated stock concentration  

6 Using the given molar absorptivity for Cr(phen)3]3+, calculate the expected A354 value for your Cr stock solution. Is this absorbance within the measurable range of the UV-vis spectrophotometer Based on the precision of the spectrophotometer, what is the precision of your calculated concentration  

8 How can you confirm that the volumetric pipettes you will be using are operating correctly  

9 What could happen if either the stock solutions or sample solutions were left in unsealed containers How might this affect your experiment  

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