A new element, Thorsonium, has two isotopes. Thorsonium isotopes have a mass of 255 amu and 257 amu. Given the average atomic mass of Thorsonium is 255.65 amu, calculate the percent abundance for each Thorsonium isotope.

255 amu has relative abundance 67.5% and 257 has relative abundance 32.5%

Explanation:

Average atomic mass =sum of product of atomic mass and relative abundance all divided by hundred or total abundance

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