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zsteed
why is it necessary to use weighted values for calculating average atomic mass?
umm according to me ,the nuetrons and protons do not have the same weight..neutrons have wt slightly greater than 1 amu & proton is exactly 1 amu ..hence the sum of no. of protons & neutrons will not give the exact weight of the atom hence we use weighed values to calculate average atomic mass..
because isotopes do not occur in 1:1 ratios, so you have to take into account the percentage at which they do exist in nature