Final answer:
The mass of one molecule of Vitamin B12 is 8.167 x 10^26 grams/mol.
Step-by-step explanation:
The mass of one molecule of Vitamin B12 can be found by using the formula M = NAM, where M is the molar mass of Vitamin B12, N is Avogadro's number, and AM is the mass of one molecule. The molar mass of Vitamin B12 is 1355.38 g/mol, and Avogadro's number is 6.022 x 10^23 molecules/mol. Substituting these values into the formula, we get M = (6.022 x 10^23 molecules/mol) x (1355.38 g/mol) = 8.167 x 10^26 g/molecule.