Question

1. Because NaBH4 is a mild reducing agent, it must be used with a protic solvent such as methanol to facilitate the reaction. This results in a side reaction between the borohydride and the methanol resulting in the production of hydrogen gas (the fizzing you observed during the addition of the reagent. Use curly-arrows to show the Bronsted acid-base reaction of one equivalent of BH4 - with methanol.

2. For the reason shown above, a fair excess of sodium borohydride was used. Neglecting the reaction of the borohydride with methanol, what mass of sodium borohydride would be required for complete reaction of 5.10g of vanillin according to the first balance equation above? SHOW YOUR WORK

Answer 1

--- 4,97 + 8 + HB-H H ***** -ske a wc-item HC-06-> B-H adduct Balanced equation is Свск + NABH + 4 H - T OCH + H3BQ + NAOH OH OCH₂ vanillin (mwi 152,15 g/mol) 14-moll (1 mel) moles Vanillin = 5.109 2 152.15 g/mol = 0.03351955 307 mol moles Na BH, Yequired = 5 P =0.008379899 26 mol mass NaBtly required = moles Na BHy x molar mass of NaButy = 0.0053798342€ mol x 37.84 g/mol mass 4 was Hy required < 0.317 9| Hope this helped you Thank you so much! Please Rate this ansper as you wish!