atomic weights and isotopes

atomic weights and isotopes - There are only three...

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CHE103 Exercise in atomic weights and isotopes Calculate the atomic mass of magnesium from the following isotope data: Isotope Mass Fractional abundance 24 Mg 23.9850 u 0.7899 25 Mg 24.9858 u 0.1000 26 Mg 25.9816 u 0.1101 Answer: at wt Mg = 24.305 u Calculate the fractional abundance of the 28 Si isotope from the following data.
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Unformatted text preview: There are only three isotopes. The fractional abundance of the 29 Si isotope is given: 0.04685. The atomic weight of Si is 28.0855 u Isotope Mass Fractional abundance 28 Si 27.976926 u ? 29 Si 28.976494 u 0.04685 30 Si 29.973770 u ? Answer: fraction 28 Si = 0.9222 ( or, 92.22 %)...
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