Gadolinio (Gd): Bohr Model, Protons, Neutrons & Electrons
Gadolinio is element number 64, a lanthanide in the f-block (the lanthanide row drawn below the table), period 6. Its atom has 64 protons, 94 neutrons and 64 electrons arranged in 6 shells: 2, 8, 18, 25, 9, 2.
- 64 protons
- 94 neutrons
- 64 electrons
Protons, neutrons and electrons in gadolinium
El atomic number of gadolinium is 64, so every gadolinium atom has 64 protons. A neutral atom has the same number of electrons, 64. The number of neutrons depends on the isotope: neutrons = mass number − atomic number. For gadolinium-158, that is 158 − 64 = 94 neutrons. Gadolinium has 7 stable isotopes, with 88, 90, 91, 92, 93, 94, 96 neutrons.
How to draw the Bohr model of gadolinium
- Draw the nucleus and write 64 p⁺ y 94 n⁰ inside it.
- Draw the first shell and put 2 electrons on it (the first shell holds at most 2).
- Draw the second shell and put 8 electrons on it.
- Draw the third shell and put 18 electrons on it.
- Draw the fourth shell and put 25 electrons on it.
- Draw the fifth shell and put 9 electrons on it.
- Draw the sixth shell and put 2 electrons on it.
- Check: 2 + 8 + 18 + 25 + 9 + 2 = 64 electrons, the same as the number of protons.
From potassium onwards the shells don’t simply fill as 2, 8, 8: the fourth shell starts before the third is full, so the real arrangement above (2, 8, 18, 25, 9, 2) is the one to draw.
Electron configuration
The electron configuration of gadolinium is [Xe] 6s² 4f⁷ 5d¹. As a lanthanide it fills an inner f-subshell, and its common ion is Gd³⁺.
Key facts about gadolinium
| Symbol | Gd |
|---|---|
| Atomic number | 64 |
| Relative atomic mass | 157.25 |
| Group · period · block | f-block · period 6 |
| Tipo | Lantánido |
| State at 25 °C | solid |
| Capas electrónicas | 2, 8, 18, 25, 9, 2 |
| Electron configuration | [Xe] 6s² 4f⁷ 5d¹ |
| Electrones de valencia | varies (outer shell: 2) |
| Common ion | Gd³⁺ |
| Electronegativity (Pauling) | 1.20 |
| First ionisation energy | 6.15 eV (593 kJ/mol) |
| Atomic radius (empirical) | 180 pm |
¿Dónde gadolinium sits on the periodic table
Preguntas frecuentes
How many protons, neutrons and electrons does gadolinium have?
Gadolinium has 64 protons and 64 electrons (atomic number 64). Its most common isotope, gadolinium-158, has 158 − 64 = 94 neutrons.
What is the electron configuration of gadolinium?
[Xe] 6s² 4f⁷ 5d¹. In shells that is 2, 8, 18, 25, 9, 2.
How many valence electrons does gadolinium have?
Gadolinium is a lanthanide, so its valence electrons are spread over two shells; its outermost shell holds 2.
Where is gadolinium on the periodic table?
In the f-block (the lanthanide row drawn below the table), period 6, in the f-block. It is a lanthanide.
