Question

Recall from unit 3, the mass number is the average of ALL of the element's isotopes and it accounts for the protons and neutrons found in the atom's nucleus. Not all choices will be used. Select one mass per element.(6 points)Magnesium, Mg Molybdenum, Mo Neodymium, Nd Thallium, Tl Selenium, Se Fluorine, F

204.4 amu, 54.94 amu, 78.97amu, 47.87amu, 144.2amu, 24.31 amu, 95.95 amu, 19.00amu

Answer 1

To assign a mass number to each element listed, we will select the average atomic mass that corresponds to the most common isotopes of the respective elements:

1. **Magnesium (Mg)**: 24.31 amu
2. **Molybdenum (Mo)**: 95.95 amu
3. **Neodymium (Nd)**: 144.2 amu
4. **Thallium (Tl)**: 204.4 amu
5. **Selenium (Se)**: 78.97 amu
6. **Fluorine (F)**: 19.00 amu

Thus, the assignments are:

- Magnesium: 24.31 amu
- Molybdenum: 95.95 amu
- Neodymium: 144.2 amu
- Thallium: 204.4 amu
- Selenium: 78.97 amu
- Fluorine: 19.00 amu

Note: Select only one mass per element as requested, so this is a comprehensive listing of the assigned masses based on the most common isotopes.