8. isotope mass (u) fractional abundance\ncr - 50 49.946 (0.0435) 4.35%\ncr - 52 51.941 (0.838) 83.8%\ncr…

8. isotope mass (u) fractional abundance\ncr - 50 49.946 (0.0435) 4.35%\ncr - 52 51.941 (0.838) 83.8%\ncr - 53 52.941 (0.095) 9.5%\ncr - 54 53.939 (0.0235) 2.35%\naverage atomic mass of chromium = 51.996 amu\n9. isotope mass (u) fractional abundance\ni - 127 127.0 80%\ni - 126 126.0 17%\ni - 128 128.0 3%\naverage atomic mass of iodine =\n10. isotope mass (u) fractional abundance\nau - 197 196.56 50%\nau - 198 197.96 50%\naverage atomic mass of gold =\n11. isotope mass (u) fractional abundance\nfe - 55 54.876 14.5%\nfe - 56 55.998 85.5%\naverage atomic mass of iron =\n12. isotope mass (u) fractional abundance\nh - 1 0.98 99%\nh - 2 1.97 0.8%\nh - 3 2.98 0.2%\naverage atomic mass of hydrogen =\n13. isotope mass (u) fractional abundance\nn - 14 14.0 95%\nn - 15 15.0 3%\nn - 16 16.0 2%\naverage atomic mass of nitrogen =\n14. isotope mass (u) fractional abundance\nc - 12 12.0 98%\nc - 13 13.0 0.5%\n1.5%

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