Question

what are atomic Weights?

Answer 1

Atomic weight is the average mass of atoms of an element, calculated using the relative abundance of isotopes in a naturally-occurring element. It is the weighted average of the masses of naturally-occurring isotopes.
IT IS ALSO KNOWN AS RELATIVE ATOMIC MASS.......

Answer 2

atomic weight of an element were frist determined with reference to hydrogen Dalton,second with reference to the oxygen 16 and at the present it with reference to the carbon 12 which is arbitrarily assigned 12 units of weight.
Thus atomic weight of an element may be defined as a number which indicates how many times heavier is an average atom of that element as compared 1/12of the mass of an atom of carbon 12
At. wt. of an element =wt. of an average atom /1/12×mass of an atom carbon 12

Thus the atomic weight of element are average relative weight.Unit of atomic weight is expressed in amu .

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