Chemistry question

Question

An amino acid has a molar mass of 776.9 g mol and contains 65.34% iodine by mass. What is the number of iodine atoms per molecule of amino acid?

(A) one

(B) three

(C) four

(D)five

could you explain which option you got and why?

Answer 1

65.34% x 776.9 g = 507.63 g of iodine (I)

moles of I = 507.63 g I x 1 mol I / 126.90 g = 4.00 mols I (answer C)