21. The Dalton ( Da ) is another name for the unified atomic mass unit. 22. Samples of these elements therefore may serve as reference standards for certain atomic mass values. 23. Germanium has five naturally occurring isotopes ranging in atomic mass number from 70 to 76. 24. This single nuclide will have a characteristic atomic mass . 25. Its relative atomic mass should be around 445 u. 26. Atomic mass figures are thus commonly reported to many more significant figures than atomic weights.27. The desorbing NO was measured using a mass spectrometer monitoring the atomic mass of 30. 28. There are 21 known radioisotopes with atomic masses ranging from 232 Cm to 252 Cm. 29. An accurate atomic mass for samples of lithium cannot be measured for all sources of lithium. 30. Dysprosium also has at least 11 metastable isomers, ranging in atomic mass from 140 to 165.
