Your protons are correct but it’s 28 neutrons not 27!
Answer: According to Moseley, similar properties recur periodically when elements are arranged according to increasing atomic number. Atomic numbers, NOT weights, determine the factor of chemical properties.
Mendeleev realized that the physical and chemical properties of elements were related to their atomic mass in a "periodic" way, and arranged them so that groups of elements with similar properties fell into vertical columns in his table
Answer:
Judging from the wording of he question, you mean units. If that is indeed the case, the answer is g/Mol (grams per mol)
Let me know if my interpretation is incorrect and please tell me what you are actually trying to find.
