# chemistry

90.92% of the atoms have a mass of 19.988 u, 0.26% of the atoms have a mass of 20.983 u and 8.82% of atoms have a mass of 21.978 u. Calculate the average atomic mass of this element

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1. 0.9092(19.988) + (0.0026*20.983) + (0.0882*21.978) = ??

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posted by DrBob222

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