Calculate the molarity of the nabh 4 solution that

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1. Calculate the molarity of the NaBH4solution that you prepared in step 3 above. 2. How many equivalents of hydride (H-) are you adding to vanillin in this reaction? 3. Please draw a reasonable mechanism for this reaction. 4. What is the pKa of the phenolic functional group of vanillin. Predict the protonation state (e.g. is it protonated or deprotonated) of this functional group during the course of this experiment e.g. when 1. vanillin is first dissolved in ethanol. 2. After the addition of the NaBH4solution. 3. During the decomposition of excess NaBH4. 4. After isolation by filtration. Post lab questions 1. How could you modify your procedure to increase your isolated yield. 2. How did your melting point compare to the reported value? If lower, what can you do to increase the m.p. 3. Draw the NMR chemical shift splitting pattern (tree diagram) for Ha, Hband Hc, labeling the appropriate coupling constants. Assume Jbc= 1 Hz 4. If you had to use 1HNMR to verify that you actually synthesized vanillyl alcohol from vanillin, describe at least two key differences in the 1HNMR spectra of these two compounds that would support your claim. OHHOOCH3HaHbHcVanillin

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