Question

Vitamin B12, cyanocobalamin, is essential for human nutrition. It is concentrated in animal tissue but not in higher plants. Although nutritional requirements for the vitamin are quite low, people who abstain completely from animal products may develop a deficiency anemia. Cyanocobalamin is the form used in vitamin supplements. It contains 4.34% cobalt by mass. Calculate the molar mass of cyanocobalamin, assuming that there is one atom of cobalt in every molecule of cyanocobalamin.

I have no clue even where to start.

Answer 1

molmass=atomicmassCo/.0434

Answer 2

Let's see.
If Co has a mass of 58.93 and that accounts for 4.34% of the total mass, then
the molar mass of the compound must be
58.93 x (100%/4.34%) = ??
You can check this out at
http://en.wikipedia.org/wiki/Vitamin_B12

Close!

Answer 3

1355.37