Vitamin B12,cyanocobalamin,is essential for human nutrition.It is concentrated in animal tissue but

题目

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.
___________ g/mol

答案

钴的相对原子质量是59
则胡萝卜素的相对分子质量是
59/4.34%=1359.4g/mol